Pump System

ABSTRACT

A pump system that has a power end and a fluid end assembly. The fluid end assembly includes a plunger configured to translate within a plunger bore. The fluid end further includes a suction valve assembly and a discharge valve assembly. The power end is configured to use a pony rod to induce movement of the plunger within the fluid end assembly to generate a pressure differential. The suction valve assembly and the discharge assembly operate in response to the pressure differential to move the fluid. A straight valve seal is located within the suction valve assembly and/or the discharge valve assembly to distribute forces incurred by movement of valves within the fluid end assembly.

TECHNICAL FIELD

The application relates generally to pump systems having a power end in operative communication with a fluid end and, more particularly, to a pump system for delivering fracture fluids.

DESCRIPTION OF THE PRIOR ART

It is difficult to economically produce hydrocarbons from low permeability reservoir rocks. Oil and gas production rates are often boosted by hydraulic fracturing, a technique that increases rock permeability by opening channels through which hydrocarbons can flow to recovery wells. During hydraulic fracturing, a fluid is pumped into the earth under high pressure (sometimes as high as 50,000 PSI) where it enters a reservoir rock and cracks or fractures it. Large quantities of proppants are carried in suspension by the fluid into the fractures. When the pressure is released, the fractures partially close on the proppants, leaving channels for oil and gas to flow.

Specialized pump systems are used to deliver fracture fluids at sufficiently high rates and pressures to complete a hydraulic fracturing procedure or “frac job.” Positive displacement pumps used in Oil Field Well Service Applications are operated, serviced & maintained in harsh environments & operating conditions. The four main issues that contribute to reduced performance and the loss of service life in these pumps are: 1) Pump cavitation due to inadequate and or inconsistent charge flow; 2) Cracking and Failure due to metal fatigue in the pump fluid ends which are also known as the liquid or pressure sides of the pump. This is caused by the continual high pressurization & de-pressurization that occurs up to three times per second as the pump reciprocates to displace liquid under pressure; 3) Improper maintenance; and 4) Improper operation.

These pump systems are usually provided with power ends and fluid ends. Power ends induce movement of a plunger within the fluid end that places fluids under pressure. Within these fluid ends are a number of reciprocating plungers that pressurize fracture fluids. Suction valves and discharge valves control fluid flow to, and from, the plungers.

A valve that has too many internal projections can capture or “knock out” enough proppant to block the flow of fluid through a pump, requiring that time and effort be invested to clear the blockage—a costly undertaking. Also, these projections can create substantial pressure losses that require more energy to be expended than is necessary to perform hydraulic fracturing work. Commonly used discharge valves possess a number of guides or “wings” that project into the center of a valve to hold a piston in place. These wings are known to capture proppants suspended in fracture fluids. A need exists for an improved, discharge valve without wings.

Within these valves are pistons that normally press against valve seats to selectively stop the flow of fluid. Pressure differentials from the motion of the plunger typically open and close the valves. To reduce leaks around valve seats and maximize pumping efficiencies, the pistons found in suction and discharge valves are typically equipped with sealing elements. These sealing elements or inserts are typically rings formed of a resilient material. The rings are fitted into grooves in the pistons that are positioned to facilitate contact with valve seats. Typical designs of sealing elements have permitted them to move about in their retaining grooves after installation, permitting them to wear excessively in the presence of abrasive proppants and other materials carried by fracture fluids. Thus, the known sealing elements required frequent replacement.

Sealing elements are located deep within the fluid end of a pump that is held together by a large number of heavy, threaded fasteners. To access the worn sealing elements, the fluid end frequently required substantial disassembly. Although manufacturers provide strong and robust pumps, disassembly of pumps in the field is especially time-consuming and difficult to perform. Increasing the longevity of the sealing elements found in suction and discharge valves can, therefore, provide substantial cost savings to an oilfield operator.

The plungers reciprocate within a pumping chamber to produce the extremely high pressures necessary to break reservoir rocks underground. As the plungers reciprocate within the pumping chamber, the plungers cycle between high and low pressures and are subjected to high stress variations. The plungers also rub against sealing elements in the ends of the pumping chambers and, consequently, are worn and abraded by proppants and other materials carried in the pumped fluids.

These pumps often have connecting rods that join a crosshead within the power end and drive the plunger. A conventional connecting rod is cast as a single unit and is subsequently machined to its finished dimensions. When portions of such a connecting rod wear out, the rod must be replaced in its entirety—a time-consuming and costly project. Multi-piece connecting rods have been developed as a substitute for one-piece rods so as to minimize rod replacement time by permitting just the worn portions of a rod to be swapped. Multi-piece rods have not, however, gained widespread acceptance since wear tends to occur not only in the usual spots, but, also, at the junctions between the joined pieces.

These pumps have bearings that couple connecting rods to a crankshaft within the power end. These bearings usually incorporate bronze sleeves that encircle the crankshaft and prevent or limit friction. Improper design of these sleeves, however, can restrict the flow of lubricant to the surfaces contacting the crankshaft. If flow is impeded, the sleeves and the pump can be damaged. Damage can be caused by the sleeves seizing upon the crankshaft so that they grind against their housings and by galling where they wear against the crankshaft. In either case, the affected pump must be immediately shut down and the bearings repaired. Such an event can be time consuming and costly for an oilfield operator conducting a frac job.

The pump systems have many parts that are releasably fastened to one another so that they can be easily repaired or replaced. It is the connections between the parts and the supporting features within the pump system that tend to weaken the pump system, limiting its pressure rating, and making it susceptible to corrosion, leaks, and cracks under high, cyclical stresses. Thus, pump systems sometimes fail under load prematurely.

In an effort to increase pressure ratings and decrease failure rates, improved fluid ends have been proposed by pump manufacturers, however the designs have not seen widespread use or commercial success since they have been difficult and costly to make and equally difficult to service in the field. A continuing need, therefore, exists for a pump system that addresses the disadvantages described.

Although great strides have been made in pump systems, considerable shortcomings remain.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present invention, including its features and advantages, reference is now made to the detailed description of the invention taken in conjunction with the accompanying drawings in which like numerals identify like parts, and in which:

FIG. 1 is a section view of a pump system according to the preferred embodiment of the present application;

FIG. 2 is a side elevational view of a connecting rod bearing housing mounted on a connecting rod and carrying a connecting rod bearing according to the preferred embodiment of the present application;

FIG. 3 is an exploded, cross-sectional view of the housing and rod bearing of FIG. 2;

FIG. 4 is a top view of the connecting rod bearing housing of FIG. 2;

FIG. 5 is a bottom view of the upper bearing segment carried by the housing of FIG. 3;

FIG. 6 is a top view of the lower bearing segment carried by the housing of FIG. 3;

FIG. 7 is a front elevational view of a connecting rod with portions broken away to reveal interior details thereof according to the preferred embodiment of the present application;

FIG. 8 is a side elevational view of the top portion of the connecting rod of FIG. 7 with portions broken away to reveal interior details thereof;

FIG. 9 is a bottom view of the connecting rod of FIG. 7;

FIG. 10 is a top view of the connecting rod of FIG. 7;

FIG. 11 is a schematic view showing the relative positions of the four drawing sheets carrying FIGS. 12A, 12B, 12C, and 12D, each representing corresponding portions of a first embodiment of a fluid end assembly;

FIG. 12A is a cross-sectional view of the left portion of a first embodiment of the fluid end assembly of according to the preferred embodiment of the present application;

FIG. 12B is a cross-sectional view of a central portion of the first embodiment of the fluid end assembly according to the preferred embodiment of the present application;

FIG. 12C is a cross-sectional view of an upper, right portion of the first embodiment of the fluid end assembly according to the preferred embodiment of the present application;

FIG. 12D is a cross-sectional view of a lower right portion of the first embodiment of the fluid end assembly according to the preferred embodiment of the present application;

FIG. 13 is a schematic view showing the relative positions of the four drawing sheets carrying FIGS. 14A, 14B, 14C, and 14D, each representing corresponding portions of an alternative embodiment of the fluid end assembly of FIGS. 11-12;

FIG. 14A is a cross-sectional view of the left portion of a second embodiment of the fluid end assembly of FIGS. 11-12;

FIG. 14B is a cross-sectional view of the central portion of the second embodiment of the fluid end assembly of FIGS. 11-12;

FIG. 14C is a cross-sectional view of the upper, right portion of the second embodiment of the fluid end assembly of FIGS. 11-12;

FIG. 14D is a cross-sectional view of the lower right portion of the second embodiment of the fluid end assembly of FIGS. 11-12;

FIG. 15 is a schematic view showing the relative positions of the three drawing sheets carrying FIGS. 16A, 16B, and 16C, each representing corresponding portions of an alternative embodiment of the fluid end assembly of FIGS. 11-14;

FIG. 16A is an enlarged, cross-sectional view of the top portion of the fluid end assembly of FIG. 15;

FIG. 16B is an enlarged, cross-sectional view of the middle portion of the fluid end assembly of FIG. 15;

FIG. 16C is an enlarged, cross-sectional view of the bottom portion of the fluid end assembly of FIG. 15;

FIG. 17 is a longitudinal, cross-sectional view of an alternative embodiment of the plunger assembly of FIGS. 11-14;

FIG. 18 is an exploded, side elevational view of the pony rod adapter of the plunger assembly of FIG. 17;

FIG. 19 is a bottom view of the pony rod adapter of FIG. 18;

FIG. 20 is a top view of the pony rod adapter of FIG. 18;

FIG. 21 is a cross-sectional view taken along line 21-21 of FIG. 18;

FIG. 22 is a cross-sectional view taken along line 22-22 of FIG. 18;

FIG. 23 is a cross-sectional view taken along line 23-23 of FIG. 18;

FIG. 24 is a side elevational view of the plunger of the plunger assembly of FIG. 17 with portions broken away to reveal details thereof;

FIG. 25 is a top view of the plunger of FIG. 24;

FIG. 26 is a cross-sectional view of an alternate plunger for use in the plunger assembly of FIG. 17 with portions broken away;

FIG. 27 is an outer end view of the pony rod of the plunger assembly;

FIG. 28 is a side elevational view of the pony rod with portions broken away;

FIG. 29 is a perspective view of a clamp assembly as an alternative embodiment of the pony rod adapter of FIGS. 11-14 and 17;

FIG. 30 is a partial section view of a plunger and pony rod used in with the fluid end of FIG. 29;

FIG. 31 is side view of a stud in the clamp assembly of FIG. 29;

FIG. 32 is a perspective view of a clamp in the clamp assembly of FIG. 29, the clamp having an integral deflector;

FIG. 33 is an exploded view of the clamp of FIG. 32;

FIG. 34 is a side view of an alignment pin for use within the clamp assembly of FIG. 29;

FIG. 35 is a section view of the stud of FIG. 31 in the pony rod and plunger of FIG. 30;

FIGS. 36 and 37 are illustrative section views of an alternative clamp assembly using an alternative plunger and pony rod having a flange portion;

FIG. 38 is a side elevational view of an alternate embodiment of a suction valve with portions broken away to reveal details thereof according to the present application;

FIG. 39 is a bottom view of the valve seat and guide assembly of the suction valve of FIG. 38;

FIG. 40 is a bottom view of the valve retainer of the suction valve of FIG. 38;

FIG. 41 is a side elevational view of an alternative embodiment of a discharge valve with portions broken away to reveal details thereof according to the present application;

FIG. 42 is a top view of a piston of the discharge valve of FIG. 41;

FIG. 43 is a perspective view of an alternative embodiment of a valve insert according to the present application;

FIG. 44 is a top view of the valve insert of FIG. 43 with the right-hand portion broken away;

FIG. 45 is a bottom view of the valve insert of FIG. 43 with the left-hand portion broken away;

FIG. 46 is a side elevational view of the valve insert of FIG. 43 with portions broken away to reveal details thereof;

FIG. 47 is an exploded, perspective view of the circle and quadrilateral that are superposed to form a polygon that defines the cross section of the valve insert of FIG. 43;

FIG. 48 is the polygon of FIG. 47 that is rotated about a vertical axis so as to form the valve insert;

FIG. 49 is a side elevational view of a discharge valve with portions broken away to reveal details thereof, the discharge valve comprising the valve insert of FIG. 43;

FIG. 50 is a side elevational view of a suction valve with portions broken away to reveal details thereof, the suction valve comprising the valve insert of FIG. 43;

FIG. 51 is a perspective view of a manifold used in the pump system of FIG. 1;

FIG. 52 is an end view of the manifold of FIG. 51 as seen through a connecting pipe;

FIG. 53 is an end view of the manifold of FIG. 51 adjacent a third feeder;

FIG. 54 is a section view of a top reducer pipe used in the manifold of FIG. 51;

FIG. 55 is a section view of a bottom reducer pipe used in the manifold of FIG. 51;

FIG. 56 is a perspective view of a rock screen insert in the pump system of FIG. 1 according to the present application;

FIG. 57 is a partial section view of a first suction valve with the rock screen insert of FIG. 51;

FIGS. 58 and 59 are perspective views of a second suction valve wherein the second suction valve is partially removed to illustrate the rock screen insert of FIG. 1;

FIGS. 60-67 are perspective and section views of alternative embodiments of a packing nut in the pump system of FIG. 1;

FIGS. 68-70 are views of a discharge valve guided assembly and a suction valve guided assembly used in the fluid ends of FIGS. 15-16;

FIG. 71 is an embodiment of a discharge valve guide for use in the fluid end of FIGS. 11-14;

FIGS. 72-76 are assorted views of an embodiment of a suction valve guide assembly used in the fluid end of FIGS. 11-14;

FIG. 77 is a perspective view of a straight seal used in the pump system of FIG. 1;

FIGS. 78-79 are views of a seat deck for housing the straight seal of FIG. 77 in the fluid ends used in the pump system of FIG. 1; and

FIGS. 80A and 80B are front and side views of a vertical passage and a horizontal passage with sectional views showing the shape of peanut shaped bores used in the pump system of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Illustrative embodiments of the preferred embodiment are described below. In the interest of clarity, not all features of an actual implementation are described in this specification. It will of course be appreciated that in the development of any such actual embodiment, numerous implementation-specific decisions must be made to achieve the developer's specific goals, such as compliance with system-related and business-related constraints, which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming but would nevertheless be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure.

In the specification, reference may be made to the spatial relationships between various components and to the spatial orientation of various aspects of components as the devices are depicted in the attached drawings. However, as will be recognized by those skilled in the art after a complete reading of the present application, the devices, members, apparatuses, etc. described herein may be positioned in any desired orientation. Thus, the use of terms to describe a spatial relationship between various components or to describe the spatial orientation of aspects of such components should be understood to describe a relative relationship between the components or a spatial orientation of aspects of such components, respectively, as the device described herein may be oriented in any desired direction.

The pump system of the present application will be understood, both as to its structure and operation, from the accompanying drawings, taken in conjunction with the accompanying description. Several embodiments of the pump system and its associated components or parts are presented herein. It should be understood that various components, parts, and features of the different embodiments may be combined together and/or interchanged with one another, all of which are within the scope of the present application, even though not all variations and particular embodiments may be specifically illustrated in the drawings.

Furthermore, the associated components and parts will be described and numbered with a numerical identifier on multiple sets of drawings with respect to individual embodiments of the pump system. The numerical identifiers may vary between embodiments. When done, it is understood that such renumbered components or parts will retain a similar form and function throughout all sets of drawings despite the varied numerical identifiers.

Referring to FIG. 1 in the drawings, a pump system 1 according to the preferred embodiment is illustrated. Pump system 1 includes a power end 2 and a fluid end 10. Power end 2 is configured to have a crankshaft 3 coupled to a connecting rod 4 and bearings 5. The bearings having crosshead sleeves 6 to improve bearing life and permit fully pressurized lubrication. Power end 2 is configured to drive a pony rod that is coupled to a plunger 7 with a pony rod adapter 8 within fluid end 10. As plunger 3 reciprocates within fluid end 10, a suction valve 9 a and a discharge valve 9 b are operated according to pressure differentials generated from reciprocating movement of plunger 7. Suction valve 9 a receives pumping fluid through a suction or supply manifold 28. The accompanying description will detail various portions of pump system 1.

Connecting Rod Bearing

Referring now also to the FIGS. 2-6, a connecting rod bearing housing in accordance with the present application is shown at 1010. Housing 1010 includes an attaching portion 1012 for fastening to the bottom of a connecting rod 1014. Housing 1010 also has a retaining portion 1016 that is fastened to attaching portion 1012 to form a ring-like assembly sized to accept a bearing 1018. Bearing 1018 has an upper segment 1020 that is carried within attaching portion 1012 and a lower segment 1022 that is carried within retaining portion 1016. In use, a crankshaft 1024, of a high-pressure pump passed through segments 1020 and 1022, freely rotates within housing 1010.

Attaching portion 1012 resembles an inverted “U” when viewed from the front. In this regard, attaching portion 1012 has a top plate 1026 and a pair of downwardly extending arms 1028 that are affixed to the opposite sides of top plate 1026. Together, plate 1026 and arms 1028 are configured to define a cylindrical concavity 1030 in the bottom of attaching portion 1012 for snugly, yet releasably, receiving upper segment 1020 of bearing 1018. Cylindrical concavity 30 has a central, longitudinal axis 1032.

An upwardly extending, alignment bore 1034 is provided in the bottom of each of arms 1028. Each bore 1034 is helically threaded to accept the threaded shaft 1036 of a bolt 1038. Each bore 1034 includes a lower, countersunk part 1040 of increased diameter at its bottom end within which an alignment washer 1042 positioned on threaded shaft 1036 is set. Each bore 1034 is located in an arm 1028 so that countersunk part 1040 intersects a side of concavity 1030. Thus, when positioned in countersunk part 1040, a washer 1042 with a sufficient height and diameter projects downwardly from the bottom of an arm 1028 and inwardly into concavity 1030.

A pair of upwardly extending, attachment bores 1044 is provided in the bottom of each of arms 1028. As shown, one of bores 1044 is positioned in front of alignment bore 1034 and the other of bores 1044 is positioned to the rear of alignment bore 1034. Each of bores 1044 is helically threaded to accept the threaded shaft 1046 of a bolt 1048 for the releasable fastening of retaining portion 1016 to attaching portion 1012 as will be described more fully below. With the centers of alignment bores 1034 positioned the same small distance in front of a lateral axis 1050, oriented at right angles to axis 1032 midway between the front and back of attaching portion 1012, it can be seen that attachment bores 1044 in each arm 1028 are positioned on opposite sides of bore 1034, equidistantly from axis 1050.

To keep attachment portion 1012 centered on connecting rod 1014, an alignment plug 1052 extends upwardly from the top of top plate 1026. Alignment plug 1052 is integrally formed with top plate 1026 for strength. Plug 1052 is cylindrical in form so as to fit snugly into a close-fitting socket 1054 of circular outline in the bottom of connecting rod 1014.

A pair of downwardly extending, alignment bores 1056 is provided in the top of attachment portion 1012. Bores 1056 are aligned with respect to axes 1032 and 1050. As shown, bores 1056 are positioned on a plane that extends vertically upward through axis 1050. When viewed from above, bores 1056 are also seen to be equidistantly spaced from axis 1032 for balance.

Bores 1056 penetrate plug 1052 to pass into top plate 1026. Each of bores 1056 has a lower, helically threaded part 1058 for accepting the threaded shaft of a bolt 1064. Also, each of bores 1056 includes an upper, countersunk part 1060 of increased diameter for receiving an alignment pin 1066.

Each of a pair of alignment pins 1066 includes a disk 1068 sized for positioning within a countersunk part 1060. Disk 1068 has a central opening 1070 sized for the passage of a threaded shaft 1062. Projecting upwardly from the periphery of disk 1068 is a cylindrical, side wall 1072 having a height sufficient to project from countersunk part 1060 when disk 1068 is fully inserted therein. The inner diameter of side wall 1072 is sufficient to receive the enlarged head 1074 of a bolt 1064 therein. So, when bolt 1064 is tightened, head 1074 presses downwardly on the top of disk 1068, fastening alignment pin 1066 to top plate 1026.

Top plate 1026 is provided with a number of downwardly extending, helically threaded bores 1076 and 1078 positioned around plug 1052 through which bolts 1080 are passed downwardly to attach bearing housing 1010 to connecting rod 1014. As shown, three bores 1076 and 1080 are positioned on opposite sides of axis 1032. The central bores 1076 are centered on a vertical plane extending through axis 1050. The lateral bores 1078 are positioned equidistantly from axis 1050.

Retaining portion 1016 resembles the letter “U” when viewed from the front. Retaining portion 1016 has a pair of arms 1082 that are affixed together at a location that serves as the bottom of housing 1010. Arms 1082 extend upwardly and outwardly from their junction with one another and terminate at top ends that are reinforced by outwardly extending flanges 1084. Arms 1082, together, define an upwardly opening, cylindrical concavity 1086 in the top of retaining portion 1016. Concavity 1086 has the same radius of curvature as concavity 1030 in attaching portion 1012 and is similarly aligned with axis 1032. Lower segment 1022 of bearing 1018 is fitted into concavity 1086.

A downwardly extending, alignment bore 1088 is provided in the top of each of arms 1082 and is adapted for registration with a respective one of alignment bores 1034 in attaching portion 1012 when attaching portion 1012 and retaining portion 1016 are mated together. The bottom part 1090 of each bore 1088 is sized to accept the enlarged head 1092 of a bolt 1038. Additionally, each bore 1088 includes a top, countersunk part 1094 within which the bottom portion of an alignment washer 1042 held by bolt 1038 onto attaching portion 1012 is snugly set. Each bore 1088 is located in an arm 1082 so that countersunk part 1094 intersects a side of concavity 1086. When positioned in countersunk part 1094, a washer 1042 of sufficient size projects inwardly into concavity 1086.

A pair of upwardly extending, attachment bores 1096 is provided in the top of each of arms 1082 for registration with bores 1044 in attaching portion 1012. One of bores 1096 is positioned forward of alignment bore 1088 and the other of bores 1096 is positioned rearward of alignment bore 1088. Each of bores 1096 is sized to accept the threaded shaft 1046 of a bolt 1048 passed upwardly through retaining portion 1016. The bores 1096 in each arm 1082 are positioned on opposite sides of bore 1088, equidistantly from axis 1050. The enlarged heads 1098 of bolts 1048 engage the bottoms of flanges 1084 when bolts 1048 fasten attaching portion 1012 and retaining portion 1016 together.

Bearing 1018 is assembled from upper segment 1020 and lower segment 1022, each resembling one-half of a tube cut lengthwise. Each of the opposed, free ends of segment 1020 is provided with a circular notch 1100 that engages a washer 1042 projecting into concavity 1030. Also, each of the opposed, free ends of segment 1022 is provided with a circular notch 1102 that engages a washer 1042 projecting into concavity 1086. Each washer 1042, therefore, serves as a stop to prevent the rotation of upper segment 1020 and lower segment 1022 within housing 1010.

Bearing 1018 has features to distribute a liquid lubricant. Each of the opposed, free ends of upper segment 1020 are provided with a beveled area 1104 adjacent notch 1100. Additionally, each of the opposed, free ends of lower segment 1022 are provided with a beveled area 1106 adjacent notch 1102. When positioned side-by-side, beveled areas 1104 and 1106 form a lubricant reservoir extending from the front to the back of bearing 1018. A channel 1108 extends circumferentially around lower segment 1022 to connect both beveled areas 1106 together. Channel 1108 provides a lubricant distribution pathway and ensures that the lubricant reservoirs formed from beveled areas 1104 and 1106 always contain similar quantities of lubricant under similar pressures.

Bearing housing 1010 is attached to connecting rod 1014 and installed in a pump with conventional tools. When the pump is running, bearing 1018 is supplied with pressurized lubricating oil via passageways within the crankshaft 1024 encircled by bearing 1018. This oil fills channel 1108 which distributes the oil to the reservoirs formed between beveled areas 1104 and 1106. In this way, large volumes of oil are kept between the crankshaft 1024 and bearing 1018 tending to: minimize the Frictional forces acting upon bearing 1018, keep operating temperature of bearing 1018 low, and prolong the operating life of bearing 1018.

Bearing 1018 is easily removed from housing 1010 for inspection or replacement if it is thought to become worn during use in a pump. To do this, attaching portion 1012 is disconnected from retaining portion 1016 by first unscrewing bolts 1048. (An upwardly extending, helically threaded bore 1110 permits a user to gain a mechanical lock on retaining portion 1016 while bolts 1048 are removed). Then, retaining portion 1016 is pulled away from attaching portion 1012. With lower segment 1022 being free of the crankshaft 1024, it can be withdrawn from retaining portion 1016 with the application of a light pulling force. Now, by rotating the crankshaft 24 somewhat, upper segment 1020 can be pulled free of crankshaft 1024 and inspected or replaced as needed. Installing a new bearing 1018 is done by reversing the steps performed for bearing 1018 removal. Inspection and replacement of bearing 1018 can be accomplished quickly under optimal circumstances.

While bearing housing 1010 has been described in great detail, it will be appreciated by individuals having knowledge of rotary bearings that modifications can be made to housing 1010. It is understood that the description above is not limited solely to housing 1010, but encompasses any, and all, bearing housings within the scope of the following claims.

Connecting Rod

Referring now to the FIGS. 7-10, a connecting rod in accordance with the present invention is shown at 1014. Connecting rod 1014 includes a shaft 2012 having a major flange 2014 affixed to its bottom end that is adapted for releasable attachment to a bearing housing 1010. A minor flange 2018 is affixed to the top end of shaft 2012 to which a crosshead link 2020 is releasably attached.

Shaft 2012 is a hollow tube with an upper, cylindrical section 2022 and a lower, gusset section 2024 affixed to the bottom of cylindrical section 2022. Cylindrical section 2022 has a constant, outer diameter along its length. Gusset section 2024, however, has an outer diameter that gradually increases in diameter as the distance away from cylindrical section 2022 increases. Gusset section 2024 serves to reinforce major flange 2014 that is larger in size than minor flange 2018.

Shaft 2012 is provided with a weight-reducing passageway 2026 that extends longitudinally through both gusset section 2024 and cylindrical section 2022. Passageway 2026 has an elongated section bounded by a first inner wall 2028 that extends through gusset section 2024 and cylindrical section 2022. Beneath the elongated section, passageway 2026 is enlarged, being bounded by a second inner wall 2030 having an inner diameter that is greater than that of first inner wall 2028. Above the elongated section, however, passageway 2026 is restricted, being bounded by a third inner wall 2032 having an inner diameter that is less than that of first inner wall 2028. Immediately above third inner wall 2032 is a fourth inner wall 2034 having an inner diameter that is greater than that of third inner wall 2032.

The section of passageway 2026 bounded by second inner wall 2032 forms a socket for snugly receiving an alignment plug 1052 projecting upwardly from bearing housing 1010. A planar shoulder 2038 is formed in the bottom end of first inner wall 2028 at the junction of first inner wall 2028 and second inner wall 2030. A pair of alignment bores 2040, for receiving a pair of alignment pins 1066 extending upwardly from alignment plug 1052, is provided in shoulder 2038. The centers of bores 2040 define a lateral axis 2044 through shaft 2012.

The section of passageway 2026 bounded by fourth inner wall 2034 forms a socket for snugly, yet releasably, receiving an alignment pin 2046 being part of link 2020. A shoulder 2048 is formed in the top end of third inner wall 2032 at the junction of third inner wall 2032 and fourth inner wall 2034. Shoulder 2048 slopes downwardly and inwardly.

Alignment pin 2046 of crosshead link 2020 is stopped by shoulder 2048 from falling downwardly into shaft 2012. Pin 2046 is dimensioned such that it projects upwardly from shaft 2012 when it is positioned in its socket and against shoulder 2048. Pin 2046 has a solid cylindrical form with a diameter that is slightly smaller than that of fourth inner wall 2034. For proper centering and seating on the top of shoulder 2048, the bottom end of pin 2046 is tapered. (The top end of pin 2046 is similarly tapered). Pin 2046 assures the proper centering of link 2020 on shaft 2012 and that link 2020 does not creep or rotate relative to shaft 2012.

Crosshead link 2020 has a ring 2050 with a longitudinal aperture 2052 for snugly, yet releasably, receiving the top of pin 2046 extending upwardly from shaft 2012 and a transverse aperture 2054 for receiving a crosshead pin (not shown). To supply a flow of lubricating oil to the interior of aperture 2054, a lubrication opening 2056 passes through the top of ring 2050 in axial alignment with longitudinal aperture 2052 and intersects the top of transverse aperture 2054. A pair of helically threaded bores 2058 is provided on each of the opposite sides of aperture 2054 such that bores 2058 define a pattern with a square outline in the bottom of ring 2050. As shown, bores 2058 incline about 30″ from vertical and have central axes that radiate outwardly and downwardly from the central axis of aperture 2054.

Minor flange 2018 strengthens the connection between shaft 2012 and link 2020 and is integrally formed with shaft 2012. When viewed from above, minor flange 2018 is seen to have a square outline. When viewed from the side, however, flange 2018 is seen to look like a “U” with a central, shoulder portion 60, surrounding and reinforcing walls 2032 and 2034, and a pair of arm portions 62 that are affixed to the opposite sides of shoulder portion 2060 and that radiate outwardly and upwardly therefrom. Together, portions 2060 and 2062 define a cylindrical concavity 2064 in the top of flange 2018 for snugly, yet releasably, receiving ring 2050.

Each of arm portions 2062 is provided with a pair of holes 2066 for registration with a pair of bores 2058 on one side of transverse aperture 2054 in ring 2050. The threaded shafts 2068 of bolts 2070 are extended through holes 2066 and screwed into bores 2058 to releasably attach shaft 2012 to link 2020. Recesses 2072 are provided at the bottoms of holes 2066 for partially receiving the enlarged, polygonal heads 2074 of bolts 2070 that are incapable of positioning in holes 2066. When bolts 2070 are firmly tightened, the longitudinal axis 2076 of transverse aperture 2054 is oriented at right angles to lateral axis 2044 passing through the centers of alignment pin receiving holes 2040.

Major flange 2014 strengthens the connection between shaft 2012 and bearing housing 1010. Major flange 2014 has a pair of projections 2078 that extend outwardly from opposite sides of gusset section 2024 perpendicular to the longitudinal axis 2076 of transverse aperture 2054. Each of projections 2078 has three, spaced-apart holes 2080 and 2082 through which bolts 1080 are extended to attach connecting rod 1014 to bearing housing 1010. The center holes 2080 are centered on lateral axis 2044 and the remaining holes 2082 are positioned equidistantly from lateral axis 2044.

The installation of connecting rod 1014 in a pump is straightforward. First, shaft 2012 and link 2020 together with bolts 2070. Then, a crosshead pin (not shown) is extended through transverse aperture 2054 in ring 2050. Next, bolts 1080 are extended through major flange 2014 and into bearing housing 1010 previously connected to the power end of the pump, and tightened. The perfect alignment of connecting rod parts is assured by the arrangement of alignment plug 1052 and pins 1066 and 2046 and bolts 2070 and 1080. After securing all hatches and ancillary parts of the pump, the pump is ready to drive connecting rod 1014.

After the pump has been run for substantial period, ring 2050 may show signs of wear around aperture 2054 that serves as a bearing surface. (Shaft 2012 is unlikely to show any wear since there is no movement of bearing housing 1010 and relative to link 2020 during the use of connecting rod 1014). By untightening bolts 2070 and manipulating the crosshead, a worn ring 2050 can be removed from shaft 2012 and replaced by an unworn link 2020. Reinstalling bolts 2070 in the new ring 2050 permits the pump to be reenergized. Since service work does not require the removal of bearing housing 1010 from the pump, it can be completed in minimal time. Furthermore, since only the worn ring 2050 is replaced, there is no wastage of costly, machined parts.

While connecting rod 1014 has been described with a high degree of particularity, it will be appreciated by those skilled in the field that modifications can be made to it. Therefore, it must be understood that connecting rod 1014 is not limited to pumps as described, but encompasses any and all other uses.

Both connecting rod 1014 described in FIGS. 7-10 and the connecting rod bearing described in FIGS. 2-6 are configured to reduce and correct the improper and laborious maintenance of a pump system by improving access and simplifying the configurations.

Fluid End Assemblies

Referring now to FIGS. 11-14 in the drawings, a first embodiment of a fluid end assembly 10 is illustrated according to the present application. Fluid assembly 10 shows a Y-shaped intersection between plunger 16, suction valve 24, and discharge valve 26. Fluid end 10 is configured to reduce metal fatigue in the fluid end and increase ease of maintenance. In particular to FIGS. 11 and 12 of the drawings, fluid end assembly 10 includes a pump housing 12 having a plunger bore 14 within which a plunger 16 reciprocates. At its inner end, plunger bore 14 terminates in a pumping chamber 18 that is supplied with fluid from above by a suction passage 20 in pump housing 12. Fluid pressurized by plunger 16 exits pumping chamber 18 downwardly through a discharge passage 22 in pump housing 12. A suction valve 24 in suction passage 20 establishes the one-way flow of fluid from a supply manifold 28 into pumping chamber 18. A discharge valve 26 in discharge passage 22 sets up the one-way flow of fluid from pumping chamber 18 into an outlet passage 30 for release from fluid end assembly 10.

Pump housing 12 is a steel block of suitable size and shape. To lower its weight and increase its strength, housing 12 is provided with a plunger section 32 of reduced height that contains the outer end of plunger bore 14 and is adapted for attachment to the power end of a high-pressure pump 34 by a number of stay rods 36. A suction section 38, containing suction passage 20, is integrally formed with plunger section 32 and extends forwardly and upwardly from plunger section 32. Similarly, a discharge section 40, containing discharge passage 22, is integrally formed with plunger section 32 and suction section 38, and extends forwardly and downwardly from plunger section 32. Suction and discharge sections 38 and 40 generally taper from their inner ends to their outer ends.

Plunger bore 14 is provided within pump housing 12 along a centerline A. At its outer end, plunger bore 14 is widened and partly threaded at 42 to receive a compressible, packing unit 44 and a rotatable gland nut 46 that provide a fluid-tight seal around plunger 16. A number of radial apertures 45 in the gland nut 46 permit gland nut to be easily grasped by a spanner wrench (not shown) and screwed into plunger bore 14. A lubricating port 48 in plunger section 32 permits a lubricating oil to flow under the influence of gravity to plunger 16 at a point between packing unit 44 and gland nut 46 so that plunger 16 can be reciprocated without binding.

Suction passage 20 intersects the top of pumping chamber 18 and has a centerline B. Centerline B is coplanar with centerline A and intersects centerline A at a reference point Z in pumping chamber 18 to define a first obtuse angle α. Suction passage 20 extends from the bottom to the top of suction section 38. Suction passage 20 has a bottom part 20 a of relatively small diameter and a helically threaded, top part 20 b of large diameter, with each of parts 20 a and 20 b measuring about half of the length of suction passage 20. The top of part 20 a forms a deck 50 upon which a suction valve seat and guide assembly 52, being a feature of suction valve 24, rests. The innermost portion of deck 50, located closest to centerline B, is oriented at right angles to centerline B for optimally transferring forces from valve seat and guide assembly 52 to pump housing 12 so as to reduce the likelihood of fatigue-induced cracks forming in housing 12 at this location.

Discharge passage 22 intersects the bottom of pumping chamber 18 and has a third centerline C. Centerline C is coplanar with centerlines A and B that it intersects at reference point Z where there is a second obtuse angle λ formed between centerlines A and C. Additionally, discharge passage 22 has a top part 22 a of relatively small diameter and a helically threaded, bottom part 22 b of large diameter. The bottom of part 22 a forms a deck 54 upon which a discharge valve seat 56, being a feature of discharge valve 26, rests. The portion of deck 54 closest to centerline C is oriented at right angles to centerline C for optimally transferring forces from valve seat 56 to pump housing 12 in a manner that reduces the likelihood of fatigue-induced cracks forming in housing 12 at this location.

Reference point Z is placed on centerline A at a location that facilitates the movement of fluid from suction passage 20 into pumping chamber 18 and from pumping chamber 18 into discharge passage 22 as plunger 16 reciprocates from its innermost point of travel to the right of point Z in FIG. 12D to its outermost point of travel to the left of point Z in FIG. 12D. (At its innermost point of travel, illustrated in FIG. 12D, plunger 16 has passed point Z to move into both suction passage 20 and discharge passage 22. Suction valve piston 58 is provided with a concave cross section to avoid contact with plunger 16 and so is discharge valve seat 56). Obtuse angle α, measuring about 120°, is somewhat less than obtuse angle λ, measuring about 125°, to accommodate outlet passage 30 in discharge section 40. The resulting Y-shaped configuration offered by the intersections of plunger bore 14, suction passage 20, discharge passage 22 and their associated centerlines A, B and C reduces stresses within pump housing 12 during the use of fluid end assembly 10 to minimize the likelihood of pump housing 12 cracking over time and maximize the service life of assembly 10.

Outlet passage 30 passes through discharge section 40, extending from one end of discharge section to the other. A connector passage 60 intersects outlet passage 30 at right angles to place discharge passage 22 in fluid communication with outlet passage 30. To either end, or both ends, of discharge section 40 is connected one or more conduits (not shown) for carrying pressurized fluid away from outlet passage 30 and fluid end assembly 10. This pressurized fluid is used in oilfield applications to fracture subterranean rock formations. Placing outlet passage 30 away from discharge valve 26 limits the transverse or lateral flow of fluid through the discharge valve 26, especially in fluid end assemblies constructed with multiple, parallel sets of plungers 16 and valves 24 and 26. Discharge valve 26, therefore, runs without interference from turbulent flow through outlet passage 30 thereby resulting in a smoother-running and more efficient fluid end assembly 10.

Supply manifold 28 includes a tubular body 62 whose opposite ends are connected to a fluid source when assembly 10 is operated. A tubular connector 64 extends downwardly from tubular body 62 to engage the open top of valve retainer 66 of suction valve 24. The bottom of connector 64 is provided with a peripheral slot 68 and the top of valve retainer 66 is provided with a similar, peripheral slot 70. Slots 68 and 70 accommodate a VICTAULIC coupling body 72 of well-known construction for the quick and easy connection of valve retainer 66 to manifold 28. Within body 72 is positioned a VICTAULIC rubber seal 74 to prevent fluid leaks from body 72.

To permit the easy servicing of suction valve 24 without the need to fully disengage manifold 28 from assembly 10, one or more hinges 76 join manifold 28 to pump housing 12. Each hinge 76 has a mounting bracket 78 secured by one or more threaded fasteners (not shown) to pump housing 12. Mounting bracket 78 has a transverse aperture 80 that accommodates a hinge pin 82. The inner end of a swing arm 84 is pivotally attached by hinge pin 82 to mounting bracket 78. The outer end of swing arm 84 is affixed to tubular body 62. When VICTAULIC coupling body 72 is removed from assembly 10, manifold 28 is free to pivot 90° on hinge 76 to the broken line position seen in FIG. 12B.

Supply manifold 28 can be locked in a pivoted position to permit suction valve 24 to be easily serviced. To this end, a second transverse aperture 86 is provided in mounting bracket 78 adjacent first transverse aperture 80 and a third transverse aperture 88, positioned for registration with second aperture 86 when manifold 28 is in a pivoted position, is provided in swing arm 84. Locking manifold 28 in the pivoted position is afforded by extending a locking pin 90 through registered apertures 86 and 88.

Mounting bracket 78 is provided in the form of a loop or ring to serve as a lifting eye for fluid end assembly 10. By grasping bracket 78 with suitable lifting hook or chain, assembly 10 can be elevated while mounted upon power end 34 or not. Thus, assembly 10 can be safely and easily transported from place to place.

Suction valve 24 includes valve seat and guide assembly 52 tightly fitted into the bottom part 20 a of suction passage 20. A piston 58 moves within assembly 52 to control the flow of fluid through suction passage 20. Piston 58 has a head 92 for engaging the seat portion 52 a of assembly 52 and a stem 94 extending upwardly from head 92 through the guide portion 52 b of assembly 52. A valve keeper 96 is fitted upon the top of stem 94 and is retained there by a split ring 98. A compressed spring 100 is positioned between guide portion 52 b and keeper 96 for normally retaining head 92 in engagement with seat portion 52 a so as to prevent fluid flow through passage 20. Externally, helically threaded, valve retainer 66 is screwed into top part 20 b of suction passage 20 to retain the balance of valve 24 within pump housing 12 and provide for the attachment of valve 24 to manifold 28. Valve retainer 66 has a tapered inner passageway 102 with a small-diameter, orifice portion 104 that serves to maintain a fluid velocity through fluid end assembly 10 that is sufficient to prevent proppant particles carried by a pumped fluid from dropping from suspension and blocking suction valve 24. Of course, the relatively large, outer diameter of valve retainer 66 permits valve seat and guide assembly 52, piston 58, spring 100, etc., to be accessed from the exterior of pump housing 12 (once manifold 28 is pivoted out of the way and retainer 66 is disengaged from housing 12) making the servicing of suction valve 24 simpler.

Pump housing 12 is substantially strengthened by helically threading the entirety of the top part 20 b of suction passage 20. The coextensive threads on the exterior of valve retainer 66 distribute pressure loads evenly to the pump housing 12 thereby inhibiting the formation of cracks in the pump housing 12 at the bottom of top part 20 b adjacent seat deck 50 caused by cyclical loading of fluid end assembly 10.

Discharge valve 26 includes valve seat 56 positioned in top part 22 a of discharge passage 22 and a reciprocating piston 106 for controlling the flow of fluid through passage 22. Piston 106 has a head portion 108 for engaging valve seat 56 and a hollow, stem portion 110 extending downwardly from head portion 108. A valve guide 112 is positioned below piston 106 in passage 22 and has a guide rod 114 that projects upwardly into a longitudinal socket 116 provided in stem portion 110 where it is slidably received. A number of radial apertures 118 penetrate the bottom of stem portion 110 to equalize the pressures in passage 22 and socket 116. A compressed spring 120 is disposed between the valve guide 112 and head portion 108 to normally press head portion 108 into engagement with seat 56. A valve retainer 122 is screwed into the bottom part 22 b of passage 22 to retain valve 26 within pump housing 12.

Plunger assembly 124 includes a pony rod adapter 126, plunger 16 releasably attached to pony rod adapter 126, and a pony rod 128 being releasably attached to pony rod adapter 126. Pony rod adapter 126 has a first cylindrical body 130 and a number of apertures 132 penetrating first cylindrical body 130 for engagement by a first spanner wrench (not shown). A first helically threaded pin 134 is affixed to first cylindrical body 130 and projects from one of its ends. A second helically threaded pin 136 is affixed to first cylindrical body 130 and projects from the other of its ends.

Plunger 16 has a second cylindrical body 138 for reciprocating within a pumping chamber 18. Second cylindrical body 138 has a first outer end with a first helically threaded bore 140 for threadably receiving first helically threaded pin 134. Second cylindrical body 138 also has a first inner end with a socket 142 useful for supporting for body 138 at the time of its manufacture. A number of radial holes 174 are provided around the outer end of plunger 16 for engagement by a second spanner wrench (not shown). In use, with the first spanner wrench engaged with pony rod adapter 126, the second spanner wrench grasps plunger 16 and applies the torque needed to unscrew plunger 16 from pony rod adapter 126.

Pony rod 128 has a third cylindrical body 144 for reciprocating into, and out of, power end 34. Third cylindrical body 144 has a second inner end with a second helically threaded bore 146 for threadably receiving second helically threaded pin 136. Third cylindrical body 144 also has a second outer end. A peripheral flange 148 is affixed to, and extends outwardly from, the second outer end. Peripheral flange 148 is provided with a number of holes 150 through which an equal number of threaded fasteners (not shown) are extended for connecting pony rod 128 to the reciprocating components of the power end 34.

Fluid end assembly 10 pressurizes fluid by means of the reciprocating action of plunger 16. Valves 24 and 26 permit fluid pressurized by plunger 16 to move only in one direction from manifold 28 to outlet passage 30. The Y-shaped configuration of bore 14 and passages 20 and 22 in addition to the thick, tapered walls provided to plunger section 32, suction section 38, and discharge section 40 provide pump housing 12 with a construction that is robust and not prone to fail under the cyclical loading developed by plunger 16. Should plunger 16, valves 24 and 26, packing unit 44, gland nut 46, or plunger assembly 124 ever require servicing, they are easy to repair or replace with ordinary tools and without major disassembly of the fluid end assembly 10.

Referring now to FIGS. 13 and 14 of the drawings, a second embodiment of a fluid end assembly is shown at 410. Fluid end assembly 410 is substantially the same as fluid end assembly except that a suction valve 424 and a discharge valve 426, and the passages 420 and 422 for the valves 424 and 426, have been modified somewhat. These modifications are believed to further strengthen valves 424 and 424 and fluid end assembly 410.

Fluid end assembly 410 includes a pump housing 412 having a plunger bore 414 within which a plunger 416 reciprocates. At its inner end, plunger bore 414 terminates in a pumping chamber 418 that is supplied with fluid by a suction passage 420 in pump housing 412. Fluid pressurized by plunger 416 exits pumping chamber 418 through a discharge passage 422 in pump housing 412 located opposite suction passage 420. A suction valve 424 in suction passage 420 permits the one-way flow of fluid from a supply manifold 428 to pumping chamber 418. A discharge valve 426 in discharge passage 422 allows that one-way flow of fluid from chamber 418 into an outlet passage 430 for release from assembly 410.

Pump housing 412 is a steel forging. Housing 412 has a plunger section 432 that contains the outer end of plunger bore 414 and is adapted for attachment to the power end of a high-pressure pump 434 by a number of stay rods 436. A suction section 438, containing suction passage 420, is integrally formed with plunger section 432 and extends forwardly and upwardly from plunger section 432. Similarly, a discharge section 440, containing discharge passage 422, is integrally formed with plunger section 432 and suction section 438 and extends forwardly and downwardly from plunger section 432. Suction and discharge sections 438 and 440 taper from their inner ends to their outer ends.

Plunger bore 414 is provided within pump housing 412 along a first centerline A′. At its outer end, plunger bore 414 is widened and partly threaded at 442 to receive a packing unit 444 and a rotatable gland nut 446 that, together, provide a fluid-tight seal around plunger 416. A lubricating port 448 in plunger section 432 permits a liquid lubricant to flow to plunger 416 at a point between packing unit 444 and gland nut 446.

Suction passage 420 intersects plunger bore 414 and has a second centerline B′ that is coplanar with centerline A′ and intersects centerline A′ at a reference point Z′ to define a first obtuse angle α′. Passage 420 extends from the bottom to the top of suction section 438. Passage 420 has a tapered, bottom part 420 a, increasing in diameter from bottom to top with sides sloping about 15° relative to centerline A′. Passage 420 also has a helically threaded, top part 420 b of relatively large diameter.

Passage 420 has a deck 450 that serves as a guide for installing seat 452 of suction valve 424. The top of part 420 a, being of smaller diameter than the bottom of part 420 b, forms deck 450 in housing 412. The innermost portion of deck 450, located closest to centerline B′, is oriented at right angles to centerline B′. Since no portion of valve 424, described hereinbelow, rests upon deck 450 there is little likelihood of fatigue-induced cracks forming in or around deck 450.

Discharge passage 422 intersects both plunger bore 414 and suction passage 420 and has a third centerline C′. Centerline C′ is coplanar with centerlines A′ and B′ that it intersects at reference point Z′ so as to define a second obtuse angle λ′. Additionally, passage 422 has a tapered, top part 422 a, increasing in diameter from top to bottom with sides sloping about 15° relative to centerline C′. Passage 422 also has a medial part 422 b of somewhat greater diameter than the bottom of part 422 a. Finally, passage 422 has a helically threaded, bottom part 422 c having a diameter greater than that of part 422 b.

Passage 422 has a deck 454 that serves as a guide for installing seat 456 of discharge valve 426. The bottom of part 422 a, being of smaller diameter than the top of part 422 b, forms deck 454 in housing 412. The innermost portion of deck 450, located closest to centerline C′, is oriented at right angles to centerline C′. Since no portion of valve 426, described hereinbelow, rests upon deck 454 there is little likelihood of fatigue-induced cracks forming in or around deck 454.

Reference point Z′ is placed on centerline A′ at a location that facilitates the movement of fluid from pumping chamber 418 into discharge passage 422 as plunger 416 reciprocates from its innermost point of travel to the right of point Z′ in FIGS. 14B and 14C to its outermost point of travel to the left of point Z′ in FIGS. 14B and 14C. (At its innermost point of travel, illustrated in FIGS. 14B and 14C, plunger 416 passes point Z′ to pass into both suction passage 420 and discharge passage 422 and penetrates suction valve 424 and discharge valve 426. Suction valve piston 458 is provided with a concave cross section to avoid contact with plunger 416 and discharge valve seat 456 is similarly open). Obtuse angle α′, measuring about 120°, is somewhat less than obtuse angle λ′, measuring about 125°, to accommodate outlet passage 430. The resulting Y-shaped configuration offered by the intersections of plunger bore 414, suction passage 420, discharge passage 422 and their associated centerlines A′, B′ and C′ reduces stresses within pump housing 412 during use.

Outlet passage 430 extends through discharge section 440. A connector passage 460 intersects outlet passage 430 at right angles to place discharge passage 422 in fluid communication with outlet passage 430. To either end of discharge section 440 can be connected one or more conduits (not shown) to carry pressurized fluid away from outlet passage 430 and assembly 410. Placing outlet passage 430 away from discharge valve 426 in an unconventional manner keeps the flow of fluid over and around the discharge valve 426 to a minimum, limiting vibrations.

Supply manifold 428 includes a tubular body 462 whose opposite ends are connected to a fluid source when assembly 410 is in operation. A tubular connector 464 extends downwardly from tubular body 462 to engage the open top of valve retainer 466 of suction valve 424. The bottom of connector 464 is provided with a peripheral slot 468 and the top of valve retainer 466 is provided with a similar, peripheral slot 470. Slots 468 and 470 accommodate a VICTAULIC coupling body 472 for the connection of valve retainer 466 to manifold 428. Within body 472 is positioned a VICTAULIC rubber seal 474.

To permit the easy servicing of suction valve 424 without the need to fully disengage manifold 428 from assembly 410, one or more hinges 476 join manifold 428 to pump housing 412. Each hinge 476 has a mounting bracket 478 secured by one or more threaded fasteners (not shown) to pump housing 412. Mounting bracket 478 has a transverse aperture 480 that accommodates a hinge pin 482. The inner end of a swing arm 484 is pivotally attached by hinge pin 482 to mounting bracket 478. The outer end of swing arm 484 is affixed to tubular body 462. When VICTAULIC coupling body 472 is removed from assembly 410, manifold 428 can pivot 90° on hinge 476 to the broken line position seen in FIG. 14C.

Supply manifold 428 can be secured in a pivoted position to permit suction valve 424 to be easily serviced. To this end, a second transverse aperture 486 is provided in mounting bracket 478 adjacent first transverse aperture 480 and a third transverse aperture 488, positioned for registration with second aperture 486 when manifold 428 is in a pivoted position, is provided in swing arm 484. Locking manifold 428 in the pivoted position is afforded by extending a locking pin 490 through registered apertures 486 and 488.

Mounting bracket 478 is provided in the form of a loop or ring to serve as a lifting eye for fluid end assembly 410. By grasping bracket 478 with suitable lifting apparatus, assembly 410 can be elevated while mounted upon power end 434 or not. Thus, assembly 410 can be safely and easily transported.

Suction valve 424 includes a funnel-shaped, valve seat 452 positioned in the bottom part 420 a of suction passage 420. As shown, seat 452 has an outside surface 453 that slopes downwardly and inwardly at an angle of about 15° relative to axis B′ and fits flush against bottom part 420 a. A pair of O-ring seals 455 is inset into outside surface 453 to prevent fluid from leaking around seat 452. Seat 452 also has an inside surface 457 that is substantially parallel to outside surface 453 that channels flowing fluid toward an opening of predetermined size in the bottom of seat 452 that serves as an orifice to regulate the rate of flow of fluids through suction valve 424. The bottom surface 459 of seat 452 slopes upwardly and inwardly toward axis B′ at an angle of about 45° and the top surface 461 of seat 452 is oriented at right angles to axis B′. Around the inside of top surface 461, seat 452 is provided with a peripheral channel 463.

A valve guide 465 is positioned atop valve seat 452. Valve guide 465 includes an outer ring 467 and an inner ring 469 connected together by a number of radial fins 471. Outer ring 467 fits snugly within peripheral channel 463 and extends upwardly therefrom. Ring 467 has a circumferential flange 473 that projects outwardly from the top thereof to engage top surface 461. A pair of O-ring seals 475 is inset into the top and bottom of flange 473 to prevent fluid leaks around ring. Ring 467 has a inside surface 477 that slopes downwardly and inwardly at a somewhat shallower angle than inside surface 457 to direct fluid toward valve seat 452.

Inner ring 469 is centrally positioned within outer ring 467. Ring 469 has an interior surface 479 for slidably engaging the stem 494 of a piston 458 and an exterior surface 481. Extending outwardly from the bottom of exterior surface 481 is a radial flange 483 that serves as an abutment for the top of a compressed spring 500.

Inner ring 469 and outer ring 467 are connected together by a number of fins 471 integrally formed therewith. Fins 471 radiate outwardly from flange 483 at 120° intervals and connect to inside surface 481. Fins 471 are relatively thin and present a minimal impediment to the flow of fluids through valve 424.

Piston 458 moves against valve seat 452 to control the flow of fluid through suction passage 420. Piston 458 has a head 492 for engaging seat 452 and a stem 494 extending upwardly from head 492 and through inner ring 469. A peripheral groove 485 is provided around the free end of stem 494 for grasping piston 458 from the exterior of fluid end assembly 410 during installation of valve 424. Another peripheral groove 487 is provided in stem 494 a short distance below groove 485.

A valve keeper 496 is fitted over the top of stem 494 and has a conical configuration. Keeper 496 is conical and has an exterior diameter that decreases from its top to its bottom. Extending outwardly from the top of keeper 496 is a peripheral rim 489 that serves as an abutment for the top of spring 500.

A recess 491 is provided in the top of keeper 496 for snugly receiving split ring 498 that is fitted into groove 487 in stem 494. To ensure that split ring 498 does not slide from recess 491, split ring 498 is outfitted with an inset O-ring 495. O-ring 495 serves as a safety feature to wedge keeper 496 and split ring 498 together even if spring 500 breaks thereby reducing the likelihood that piston 458 will come loose during the use of valve 424 and engage plunger 416.

Compressed spring 500 is positioned between flange 483 and rim 489 for normally retaining head 492 in engagement with seat 452 to prevent fluid flow through passage 420. Spring 500 is, however, resilient enough to permit the piston 458 to move away from seat 452 and permit the entry of fluid into pumping chamber 418 when plunger 416 creates a partial vacuum in pumping chamber 418.

Externally helically threaded, valve retainer 466 is screwed into top part 420 b of suction passage 420 to retain the balance of valve 424 within pump housing 412 and provide for the attachment of valve 424 to manifold 428. Valve retainer 466 has a tapered inner passageway 502 with a small-diameter, orifice portion 504 that serves to maintain a fluid velocity through fluid end assembly 510 that is sufficient to prevent proppant from dropping from suspension and preventing the normal operation of suction valve 424. Of course, the relatively large, outer diameter of valve retainer 466 permits valve seat and guide assembly 452, piston 458, spring 500, etc., to be accessed from the exterior of pump housing 412 (once manifold 428 is pivoted out of the way and retainer 466 is disengaged from housing 412) making servicing of suction valve 424 a breeze.

Pump housing 412 is substantially strengthened by helically threading the entirety of the top part 420 b of suction passage 420. The coextensive threads on the exterior of valve retainer 466 distribute pressure loads evenly to the pump housing 412 inhibiting the formation of cracks in the pump housing 412 at the bottom of top part 420 b adjacent seat deck 450.

Discharge valve 426 includes a funnel-shaped, valve seat 456 positioned in the top part 422 a of discharge passage 422. Seat 456 has an outside surface 501 that slopes downwardly and outwardly at an angle of about 15° relative to axis C′ and fits flush against top part 422 a. A pair of O-ring seals 503 is inset into outside surface 501 to prevent fluid from leaking around seat 456. Seat 456 also has an inside surface 505 that is substantially parallel to axis C′ that channels flowing fluid toward outlet passage 430. The bottom surface 507 of seat 456 slopes upwardly and inwardly toward axis C′ at an angle of about 45°, and the top surface 509 of seat 456 is rounded to receive pressurized fluid from pumping chamber 41 8. Around the outside of bottom surface 507, seat 456 is provided with a peripheral channel 51 1. Peripheral channel 51 1 has a depth sufficient to bring the bottom of outside surface 501 flush with seat deck 454.

Valve 426 has a reciprocating piston 506 controlling the flow of fluid through passage 422. Piston 506 has a head portion 508 for engaging bottom surface 507 and a hollow, stem portion 510 extending downwardly from head portion 508. A number of radial apertures 518 penetrate the bottom of stem portion 510.

A valve guide 512 is positioned below piston 506 in passage 422. Valve guide 512 has a disk-like base plate 513 that fits snugly into the middle portion 422 b of discharge passage 422. A guide rod 514 is affixed to, and projects upwardly from, the top of base plate 513 into a longitudinal socket 516 provided in stem portion 510 where rod 514 is slidably received. An internally threaded socket 515 is affixed to, and projects downwardly from, the bottom of base plate 513. Socket 515 is provided for grasping valve guide 512 to remove it from pump housing 412 during the servicing of valve 426.

The top of base plate 513 is provided with a recess 517 that extends around the bottom of guide rod 514. Recess 517 extends about half way into base plate 513 and receives the bottom of a compressed spring 520. Recess 517 has a sloping side wall to prevent the bunching of spring 520 when such is compressed by the movement of piston 506.

A peripheral channel 519 is provided in the top of base plate 513. Channel 519 is spaced outwardly from recess 517 and has about one-half the depth thereof. The width of channel 519 is about the same as its depth.

A pair of O-ring seals 521 is inset into the outside surface 523 of base plate 513. O-ring seals 521 are closely spaced and are intended to prevent leaks from discharge passage 422 past valve guide 512.

A valve retainer 522 keeps valve 426 within pump housing 412. Retainer 522 has an externally helically threaded plug 525 that is screwed into the bottom part 422 c of passage 422. A tightening stem 527 of hexagonal cross section is affixed to, and projects downwardly from, the bottom of plug 525. A wrench (not shown) grasps stem 527 so as to rotate retainer 522.

A compressed spring 520 is disposed between the valve guide 512 and head portion 508 to normally press head portion 508 into engagement with seat 456. Spring 520 loosely encircles stem portion 510. Spring is seated, at its top end against the bottom of head 508 and at its bottom end, in recess 517.

Discharge valve 426 has a liner assembly 529, disposed between valve seat 456 and valve guide 512, for minimizing the erosion of the pump housing 412 by pressurized, abrasive, proppant-bearing fluids. Liner assembly 529 has three parts: a liner 531, a liner holder 533 that engages valve seat 456, and a liner retainer 535 that engages valve guide 512. Together, the parts of liner assembly 529 closely cover the center part 422 b of discharge passage 422. Furthermore, liner 531, liner holder 533 and liner retainer 535 have a combined height and stiffness that is sufficient to permit a firm, compressive force, generated by fully screwing retainer 522 into part 422 c, to be imparted to valve seat 456. Thus, valve seat 456 cannot wobble in part 422 a since it is wedged in place.

Liner 531 is a ring having an outer surface 537 of constant diameter being slightly less than the diameter of part 422 b and an inner surface 539 that arcs inwardly at its top and bottom so as to thicken and strengthen liner 531 in these areas. An aperture 541 is provided in liner 531 for registration with connector passage 460. Aperture 541 has the same diameter as connector passage 460 so as to not impede flow into outlet passage 430.

Liner holder 533 is sized for snug positioning in peripheral channel 511. Liner holder 533 has a top surface 543 and an inside surface 545 that bear against valve seat 456. Liner holder 533 also has a bottom surface 547 that bears against liner 531. A convex, outside surface 549, having a radius of curvature that is less than that of seat deck 454 so as to not contact seat deck 454, connects top surface 543 to bottom surface 547. (By avoiding contact with seat deck 454, no additional stress is imparted to seat deck 454 by the addition of liner assembly 529 to fluid end assembly 410). A medial surface 551 connects inside surface to bottom surface 547 and provides a smooth flow transition between bottom surface 507 and inner surface 539 of liner 531.

Liner retainer 535 has a ring portion 553 that is sized for snug positioning in peripheral channel 519. A peripheral flange portion 555 is affixed to, and projects outwardly from, the top of ring portion 553. Flange portion 555 has a top surface 557 that engages the bottom of liner 531. Ring portion 553 has a top surface 559 that slopes downwardly and inwardly from top surface 557 so as to provide a smooth flow transition between liner 53 1 and the top of base plate 513.

Plunger assembly 524 includes a pony rod adapter 526, plunger 516 releasably attached to pony rod adapter 526, and a pony rod 528 being releasably attached to pony rod adapter 526. Pony rod adapter 526 has a first cylindrical body 530 and a number of apertures 532 penetrating first cylindrical body 530. A first helically threaded pin 534 is affixed to first cylindrical body 530 and projects from one of its ends. A second helically threaded pin 536 is affixed to first cylindrical body 530 and projects from the other of its ends. Plunger 416 has a second cylindrical body 538 for reciprocating within a pumping chamber 418. Second cylindrical body 538 has a first outer end with a first helically threaded bore 540 for threadably receiving first helically threaded pin 534. Second cylindrical body 538 also has a first inner end with a polygonal socket 542 for receiving a plunger key (not shown). Pony rod 528 has a third cylindrical body 544 for reciprocating into, and out of, power end 434. Third cylindrical body 544 has a second inner end with a second helically threaded bore 546 for threadably receiving second helically threaded pin 536. Third cylindrical body 544 also has a second outer end. A peripheral flange 548 is affixed to, and extends outwardly from, the second outer end. Peripheral flange 548 is provided with a number of holes 550 through which an equal number of threaded fasteners (not shown) are extended for connecting pony rod 528 to the reciprocating components of the power end 434.

A number of radial holes 574 are provided around the outer end of plunger 416 for engagement by a spanner wrench. The wrench grasps plunger 416 at the holes 574 and applies torque and pulling force as needed to remove plunger 416 from pump housing 412.

Fluid end assembly 410 produces useful work by pressurizing fluid by means of the reciprocating action of plunger 416. Valves 424 and 426 permit fluid pressurized by plunger 416 to move only in one direction from manifold 428 to outlet passage 430. The Y-shaped configuration of bore 414 and passages 420 and 422 in addition to the thick, tapered walls provided to plunger, suction and discharge sections 432, 438 and 440 pump housing 412 with a construction that is durable and not prone to fail under repeated cyclic loading developed by plunger 416. Should plunger 416, valves 424 and 426, packing unit 444 and gland nut 446, or plunger assembly 524 ever require servicing, such are easy to repair or replace with ordinary tools and without major disassembly of fluid end assembly 410.

While fluid end assemblies 410 and 10 have been described with a high degree of particularity, it will be appreciated that modifications can be made to them. For example, while operating assemblies 410 and 10 with discharge valves 426 and 26 beneath suction valves 424 and 24 is a good idea, especially in freezing weather, since it permits the assemblies to be drained of fluid with a few strokes of plungers 416 and 16, some users may elect to operate assemblies 410 and 10 in an inverted fashion with discharge valves 426 and 26 being positioned above suction valves 424 and 24. Therefore, it is to be understood that this application is not limited to fluid end assemblies 410 and 10, but encompasses any, and all, fluid end assemblies within the scope of the claims. For example, fluid ends in which the suction valve and discharge valve share a common centerline, located one directly over the other.

Referring now to FIGS. 15 and 16 in the drawings, an alternative embodiment of a fluid end assembly is illustrated. Fluid end assembly 4012 is configured to provide increased strength, durability, and fatigue resistance. Fluid end assembly 4012 has a suction valve positioned above a discharge valve so that fluid flow through the fluid end is generally downward (valve over valve configuration). The hydrostatic head of the pumped fluid in the fluid end minimizes the likelihood of cavitation as the plunger reciprocates and causes the fluid end assembly 4012 to operate with decreased vibration. Furthermore, positioning the discharge valve in a subordinate location permits the pump to be cleared of fluid with a few strokes of the plunger and avoids the risk of cracking the body of the fluid end should the pumped fluid freeze in cold weather.

Fluid end assembly 4012 includes an access port for gaining access to the inner end of the plunger and providing passage for the suction valve seat during assembly or servicing of the fluid end. A two-part plug having an inner, access pin and an outer, retaining nut closes the access port. The access pin is provided with a concavity at its inner end for receiving therein the inner end of the plunger when the plunger reaches its innermost point of travel into the body of the fluid end.

Fluid end 4012 has a body 4010 as shown. Body 4010 has a horizontal, plunger passage 4014 that extends from its front to its back. Body 4010 also has a horizontal, outlet passage 4016 that extends from one of its sides to the other and that is positioned beneath, and oriented at right angles to, plunger passage 4014. A suction passage 4018 extends vertically downward from the top of body 4010 to intersect plunger passage 4014 and to define a pumping chamber 4020 at the point of intersection. A discharge passage 4022 extends vertically downward from pumping chamber 4020 to the bottom of body 4010 and past outlet passage 4016, A horizontal, connector passage 4024 places discharge passage 4022 and outlet passage 4016 in fluid communication with one another.

Body 4010 is a metallic block, a machined forging. To lower its weight and increase its strength, body 4010 is provided with a plunger section 4026 of reduced height that contains the outer end of plunger passage 4014 and is adapted for attachment to the power end of a high-pressure pump by a plurality of stay rods (not shown). A suction section 4028, containing suction passage 4018, is integrally formed with plunger section 4026 and extends forwardly and upwardly from plunger section 4026. Likewise, a discharge section 4030, containing discharge passage 4022, outlet passage 4016 and connector passage 4024, is integrally formed with plunger section 4026 and suction section 4028 and extends forwardly and downwardly from plunger section 4026. Suction section 4028 and discharge section 4030 both taper from their inner ends to their outer ends.

Plunger passage 4014 is provided along a first centerline A extending through body 4010. At its back end, plunger passage 4014 is increased in diameter and is helically threaded at 4032 to receive a compressible, packing unit 4034 and a correspondingly helically threaded, gland nut 4036 that provide a fluid-tight seal around a plunger assembly 4038 that reciprocates in plunger passage 4014. At its front end, plunger passage 4014 is similarly increased in diameter and is helically threaded at 4040 to receive a correspondingly helically threaded plug 4042. A plug deck or shoulder 4044 is formed at the inner end of threaded portion 4040 that serves as a stop to prevent the continued inward movement of plug 4042 into plunger passage 4014.

A small-diameter, lubricating port 4046 extends vertically downward from the top of body 4010 to intersect the back end of plunger passage 4014. More particularly, lubricating port 4046 passes through plunger section 4026 and connects with plunger passage 4014 at the inner end of threads 4032. In use, port 4046 permits lubricating oil to flow to plunger assembly 4038 at a point between packing unit 4034 and gland nut 4036.

Suction passage 4018 has a second centerline B that is coplanar with centerline A and intersects centerline A at a reference point Z in pumping chamber 4020 at right angles. Suction passage 4018 extends from the top to the bottom of suction section 4028. Suction passage 4018 has a narrowed, middle part 4018 a near its midpoint that connects a helically threaded, top part 4018 b to a smooth-walled, bottom part 4018 c. The bottom of middle part 4018 a defines a suction valve seat deck 4048. The top of middle part 4018 a is a terraced surface that defines a suction valve retainer deck 4050 and a somewhat smaller diameter, suction valve guide deck 4051. The innermost portions of decks 4048 and 4050, located closest to centerline B, are oriented at right angles to centerline B to reduce the likelihood of fatigue-induced cracks forming in body 4010 at these locations. Thus, the top surface of seat deck 4048 is horizontal.

Discharge passage 4022 is centered on centerline B below suction passage 4018 and intersects plunger passage 4014 at right angles. Discharge passage 4022 has a tapered, top part 4022 a of generally small diameter, and a middle part 4022 b of a somewhat greater diameter, and a helically threaded, bottom part 4022 c of even greater diameter. The bottom of part 4022 a forms a discharge valve seat deck 4052. Similarly, the bottom of part 4022 b forms a discharge valve guide deck 4054. The innermost portions of decks 4052 and 4054, located closest to centerline B, are oriented at right angles to centerline B to reduce the likelihood of fatigue-induced cracks forming in body 4010 at these locations. The top surface of seat deck 4052 is, thus, horizontal.

Reference point Z is placed on centerline A at a location that facilitates the movement of fluid from suction passage 4018 through pumping chamber 4020 and into discharge passage 4022 while plunger assembly 4038 reciprocates from its innermost point of travel (its solid-line position to the right of point Z in FIGS. 16A and 16B) where it penetrates plug 4042 to its outermost point of travel to the left of point Z. The crossing of centerlines A and B at right angles reduces stresses within body 4010 during use and reduces the likelihood of body 4010 cracking.

Outlet passage 4016 extends across discharge section 4030. Connector passage 4024 intersects outlet passage 4016 at right angles to place discharge passage 4022 in fluid communication with outlet passage 4016. To either end of discharge section 4030 can be connected one or more conduits (not shown) to carry pressurized fluid away from outlet passage 4016 and fluid end 4012. This pressurized fluid is used, in a typical operation, to fracture subterranean rock formations. Placing outlet passage 4016 away from a discharge valve 4056 in discharge passage 4022 limits the transverse flow of fluid over the discharge valve 4056, especially in triplex and quintuplex pumps where three or five sets of passages, plungers and valves are provided in a given fluid end. Discharge valve 4056, therefore, runs without interruption or interference from jets of pumped fluids flowing through outlet passage 4016 resulting in a smoother-running and more efficient fluid end 4012.

Supply manifold 4058 delivers fluid to fluid end 4012 through suction passage 4018. Manifold 4058 includes a tubular body 4060 whose opposite ends are connected to a fluid source when fluid end 4012 is operated. A tubular connector 4062 extends downwardly from tubular body 4060 to engage the open top of valve retainer 4064 of a suction valve 4066 positioned in suction passage 4018. The bottom of connector 4062 is provided with a peripheral slot 4068 and the top of valve retainer 4064 is provided with a similar, peripheral slot 4070. Slots 4068 and 4070 accommodate a VICTAULIC coupling body 4072 of well known construction for the quick and easy connection of manifold 4058 to valve retainer 4064. Within body 4072 is positioned a VICTAULIC rubber seal 4074 to prevent fluid leaks from coupling body 4072.

To permit the easy servicing of suction valve 4066, one or more hinges 4076 join manifold 4058 to pump body 4010. Each hinge 4076 has a mounting bracket 4078 secured by one or more threaded fasteners (not shown) to body 4010. The inner end of a swing arm 4080 is pivotally attached by hinge pin 4082 to mounting bracket 4078. The outer end of swing arm 4080 is affixed to tubular body 4060. When VICTAULIC coupling body 4072 is removed from fluid end 4012, manifold 4058 is free to pivot 90° on hinges 4076 to the broken line position seen in FIG. 16A.

Suction valve 4066 includes tubular features that permit the passage of fluids and support the action of other features. For example, valve 4066 has a valve seat 4084 that, during its installation in body 4010, is moved through pumping chamber 4020 and pressed into the bottom part 4018 c of suction passage 4018 against seat deck 4048. A suction valve guide 4086 is located immediately above valve seat 4084 and, during its installation in body 4010, is moved downwardly through suction passage 4018 and engaged with guide deck 4051. An externally helically threaded, suction valve retainer 4088 is screwed downwardly into the threaded, top part 4018 b of suction passage 4018 until engaged with retainer deck 4050. Valve retainer 4088 has a tapered inner passageway 4090 with a small-diameter, orifice portion 4092 that serves to maintain a fluid velocity through fluid end 4012 that is sized to prevent a proppant from dropping out of suspension from a pumped fluid in a manner that might clog suction valve 4066. Neither seat 4084, nor guide 4086, nor retainer 4088 moves during the normal operation of fluid end 4012.

Suction valve 4066 has moving features that act in concert with seat 4084, guide 4086, and retainer 4088. A piston 4092 reciprocates within seat 4084 and has a head 4094 that engages seat 4084 to control the flow of fluid through suction passage 4018. Piston 4092 also has and a stem 4096 that extends upwardly from head 4094 through guide 4086. A valve keeper 4098 is fitted upon the top of stem 4096 and is retained there by a split ring 4100. A compressed spring 4102 is positioned between guide 4086 and keeper 4098 for normally retaining head 4094 in engagement with seat 4084. Only when the fluid pressure in suction passage 4018 is higher than that in pumping chamber 4020 will piston 4092 move against force of spring 4102 to allow fluid to move through suction passage 4018 into pumping chamber 4020.

Discharge valve 4056 includes valve seat 4104 positioned in top part 4022 a of discharge passage 4022 and a reciprocating piston 4106 for controlling the flow of fluid through passage 4022. Piston 4106 has a head 4108 for engaging valve seat 4104 and a hollow, tubular, stem 4110 extending downwardly from head 4108. A discharge valve guide 4112 is positioned below piston 4106 in passage 4022 and has a guide rod 4114 that projects upwardly into a socket 4116 provided in stem 4110 where it is slidably received. A number of radial apertures 4118 penetrate the bottom of stem 4110 to equalize pressures between passage 4022 and socket 4116. A compressed spring 4120 is disposed between the valve guide 4112 and head 4108 to normally press head 4108 into engagement with seat 4104. A discharge valve retainer 4122 is screwed into the bottom part 4022 c of passage 4022 to retain valve 4056 within body 4010. When plunger assembly 4038 is reciprocated to pressurize fluid in pumping chamber 4020, that fluid flows through seat 4104, past head 4108, and onward through discharge passage 4022. From discharge passage 4022, the pressurized fluid passes through connector passage 4024 into outlet passage 4016.

Plunger assembly 4038 includes: a pony rod adapter 4124, plunger 4126 releasably attached to pony rod adapter 4124, and a pony rod (not shown) releasably attached to pony rod adapter 4124. Pony rod adapter 4124 has a first cylindrical body 4128 and a number of apertures 4130 penetrating first cylindrical body 4128. A first helically threaded pin 4132 is affixed to first cylindrical body 4128 and projects from one of its ends. A second helically threaded pin 4134 is affixed to first cylindrical body 4128 and projects from the other of its ends. Plunger 4126 has a second cylindrical body 4136 for reciprocating within plunger passage 4014. Second cylindrical body 4136 has a first outer end with a first helically threaded bore 4138 for threadably receiving first helically threaded pin 4132. Second cylindrical body 4136 also has a first inner end with a polygonal socket 4140 for receiving a plunger key (not shown) that can be used to unscrew plunger 4126 from pony rod adaptor 4124 or turn plunger 4126 to aid in its removal from the outer end of plunger passage 4014.

The front end of plunger passage 4014 provides a port in body 4010 for gaining access to pumping chamber 4020. This access is necessary for inserting an elongated key (not shown) into socket 4140 in plunger 4126 for rotating and pushing plunger 4126 in the event that repair or replacement of plunger 4126 is needed. Access is also necessary to install or remove suction valve seat 4084 and piston 4092; so, the front end of plunger passage 4014 is sized to permit the movement of valve seat 4084 and piston 4092 through it.

Two-part plug 4042 normally closes the front end of plunger passage 4014. Plug 4042 includes an access pin 4142 and a retaining nut 4144. Access pin 4142 has a rod portion 4146 that is sized to slide snugly past plug deck 4044 and a peripheral flange portion 4148 located at the front end of rod portion 4146 that is configured to abut plug deck 4044. Rod portion 4146 has three, peripheral channels 4150 that receive O-ring seals 4152 therein to prevent pumped fluids from leaking around rod portion 4146. The front end of rod portion 4146 is provided with a concavity 4154 for reducing the weight thereof. A helically threaded bore 4156 is provided in rod portion 4146 at the center of concavity 4154 for receiving a threaded tool (not shown) for grasping and pulling pin 4142 from passage 4014. The back end of rod portion 4146 is provided with another concavity 4158 that receives the convex inner end of plunger 4126 when plunger 4126 is moved to its deepest point in plunger passage 4014 when reciprocated.

When screwed into threaded, outer portion 4040, nut 4144 presses pin 4142, and consequently rod portion 4146, inwardly with flange 4148 tightly engaging a plug deck 4044. Nut 4144 has an externally, helically threaded body 4160 that is screwed into threaded portion 4040 and a hexagonal stem 4162 that projects outwardly from threaded body 4160 that permits nut 4144 to be turned by a wrench. A concavity 4164 is provided in the back end of threaded body 4160 for reducing the weight of body 4160.

It is believed that a person having a basic knowledge of high-pressure pumps would have no trouble making and using fluid end 4012. Fluid end 4012 pressurizes fluids by the reciprocating action of plunger assembly 4038 that draws fluids from suction manifold 4058, through valve 4066, into pumping chamber 4020. From pumping chamber 4020 the continuous reciprocation of plunger assembly 4038 forces the fluids into discharge passage 4022, through discharge valve 4056, and finally through passages 4024 and 4016. Valves 4066 and 4056 keep fluid moving in a downward direction, working with gravity, through fluid end 4012, flushing proppants and minimizing the likelihood of cavitation. Fluid leaving fluid end 4012 through outlet passage 4016 can be used, in an oilfield environment, to fracture subterranean rocks.

Maintaining fluid end 4012 is easy. Access to suction valve 4066 for servicing is accomplished by removing plug 4042 from plunger passage 4014 and moving power end so that plunger 4126 is withdrawn from pumping chamber 4020. Access to discharge valve 4056 is, likewise, accomplished by unscrewing retainer 4122 from discharge 4022 and pulling the remainder of its components. The replacement of body 4010 is rare since its configuration inhibits the development of internal, stress fractures. The useful life of fluid end 4012 is, therefore, believed to be greater than that comparable fluid ends now in use.

While fluid end 4012 has been described with a high degree of particularity, it will be appreciated by some that modifications can be made to it. For example, the number and location of passages 4014, 4016, 4018, 4022 and 4024 as well as the features associated therewith can be varied. Therefore, it is to be understood that the features in this embodiment are not limited solely to fluid end 4010, but to any and all other fluid ends.

The fluid end assemblies described with respect to FIGS. 11-16 are configured to reduce and correct cracking and failure due to metal fatigue in the pump system from continual high pressurization & de-pressurization that occurs as the pump reciprocates to displace liquid under pressure.

Plunger and Pony Rod Assemblies

Referring now to FIGS. 17-28 in the drawings, a plunger assembly is illustrated. The plunger assembly is an alternate embodiment of the plunger, pony rod, and pony rod adapter described in FIGS. 11-14. A plunger 3010 and a pony rod adapter 3012 are shown to be positioned within the pumping chamber 3014 of a fluid end 3016. Fluid is drawn into chamber 3014 at low pressure through a suction valve 3020 and is pushed from chamber 3014 via a discharge valve 3018 at high pressure. The pressurization of the fluid within chamber 3014 is caused by the movement of plunger 3010 into, and out of, the open end 3022 of chamber 3014 as directed by a pony rod 3024 that projects from the power end 3026 of the pump of which fluid end 3016 is a part. Pony rod 3024 is connected to plunger 3010 by means of adapter 3012 and is reciprocated by a drive mechanism (not shown) located within the power end 3026.

As plunger 3010 is moved into chamber 3014, the fluid pressure within chamber 3014 is increased. At a predetermined point, the fluid pressure is sufficient to open discharge valve 3018 to release fluid from chamber 3014 and into discharge passage 3028 from which fluid flows from fluid end 3016 at high pressure to perform work. The amount of pressure needed to open discharge valve 3018 may be determined by a spring that keeps discharge valve 3018 closed until the threshold pressure is achieved in chamber 3014.

Plunger 3010 also creates low-pressure conditions in chamber 3014. When plunger 3010 is withdrawn from its forward-most position in chamber 3014, the fluid pressure therein decreases. As the pressure within the chamber 3014 decreases, discharge valve 3018 closes, sealing chamber 3014. Then, as plunger 3010 continues to move out of chamber 3014, the fluid pressure therein continues to drop to a point sufficient to open suction valve 3020. The opening of suction valve 3020 allows fluid to flow into chamber 3014. The amount of pressure required to open suction valve 3020 may be determined by a spring that keeps suction valve 3020 closed until the requisite low pressure is achieved in chamber 3014.

Plunger 3010 includes an elongated, cylindrical body 3030 adapted for reciprocation within chamber 3014. An enlarged bore 3032 is provided in the outer end of body 3030. Bore 3032 has a helically threaded, outer portion 3034 for threaded engagement with adapter 3012 and a non-threaded, inner portion 3036 for reducing the reciprocating weight of plunger 3010. A socket 3038 is provided in the convex, inner end of body 3030 and is axially aligned with bore 3032 at the center of body 3030. Socket 3038 has a tapered, outer part 3040 for guiding a plunger key (like an enlarged Allen key, not shown) into a correspondingly shaped, medial part 3042 of square outline. Medial part 3042 opens into a conical, inner part 3044 for aligning the tapered tip of a plunger key in socket 3038.

Although medial part 3042 of socket 3038 is shown to have a square, polygonal outline, it can have any desired outline. That outline, however, must correspond in terms of shape and size to that of the plunger key so that plunger 3010 can be prevented from rotating when adapter 3012 is turned for assembly or disassembly as described below.

Pony rod adapter 3012 includes a cylindrical body 3046 having planar, abutment surfaces 3048 and 3050 at its opposite ends for snug engagement with plunger 3010 and pony rod 3024, respectively. Between surfaces 3048 and 3050, body 3046 is penetrated by a number of apertures 3052, 3054 and 3056 spaced around the perimeter thereof, like the hour indicators on the dial of a clock, for selectively receiving a lever (not shown) for turning adapter 3012 during installation of the plunger assembly. A threaded pin 3058 projects from the center of abutment surface 3048 at the inner end of body 3046 for releasably fastening adapter 3012 to plunger 3010. Another threaded pin 3060 projects from the center of abutment surface 3050 at the outer end of body 3046 for releasably fastening adapter 3012 to pony rod 3024.

Body 3046 has three segments 3062, 3064 and 3066 with middle segment 3062 joining inner segment 3064 to outer segment 3066. As shown, middle segment 3062 has a constant outer diameter along its length. Inner segment 3064, however, has a diameter that increases evenly from its outer end proximate pony rod 3024 to its inner end where it joins with middle segment 3062. Outer segment 3066 is similarly provided with a diameter that increases evenly from its outer end where it joins middle segment 3062 to its inner end proximate plunger 3010. Body 3046, therefore, tapers, in stair step fashion, from its inner end to its outer end so as to evenly distribute loads between plunger 3010 and pony rod 3024 having a relatively smaller diameter.

Apertures 3052 are provided in the outer segment 3066 of body 3046. Apertures 3052 are provided in opposed pairs on inclined axes A1 that intersect one another at the center of body 3046. Axes A1 incline at an angle A of 30° to a vertical line V1 that also passes through the center of body 3046.

Apertures 3056 extend through both the middle segment 3062 and the inner segment 3064 of body 3046. Apertures 3056 are provided in opposed pairs on axes A2 and A3 that intersect one another at the center of body 3046. Axes A2 and A3 are oriented at right angles to one another with axis A2 corresponding in position to vertical line V1 of FIG. 21. One of apertures 3056 on axis A3 has a small diameter, inner portion 3068 that extends to the center of body 3052 where it intersects with a longitudinal bore 3070 that extends from the inner end of adapter 3012 to the outer end thereof, fully through body 3046 and pins 3058 and 3060. Inner portion 3068 and the associated bore 3056 serve to relieve the build-up of air pressure when adapter 3012 is being connected to plunger 3010 and pony rod 3024.

Apertures 3054 are positioned midway between apertures 3052 and apertures 3056 to maximize the strength of body 3046. Apertures 3054 extend through both the outer segment 3066 and the middle segment 3062 of body 3046. Apertures 3054 are provided in opposed pairs on inclined axes A4 that intersect one another at the center of body 3046. Axes A4 incline at an angle A of 60° to a vertical line V2 that passes through the center of body 3046.

Threaded pins 3058 and 3060 have helical threads that can be screwed, respectively, into tight engagement with threaded bore 3034 in plunger 3010 and a threaded bore 3072 provided in the inner end of pony rod 3024. The helical threads on pins 3058 and 3060 are the same size, but their configurations are mirror images. Thus, pin 3058 has right-handed threads and pin 3060 has left-handed threads that permit adapter 3012 to be simultaneously engaged to, or disengaged from, plunger 3010 and pony rod 3024. This double-action feature makes it a snap to replace a plunger 3010 in the event that it becomes worn during use.

Body 3046 is provided with three holes 3074 that penetrate abutment surface 3050. Holes 3074 are evenly spaced from one another around threaded pin 3060 at 120° intervals. Also, holes 3074 have a depth that is substantially equal to their diameter.

Body 3046 is provided with three holes 3076 that penetrate abutment surface 3048. Holes 3076 are evenly spaced from one another around threaded pin 3058 at 120° intervals. (These intervals are 60° out of phase with those associated with holes 3074). Also, holes 3076 have a depth that is substantially equal to their diameter.

One of a number of locking pins 3078 is snugly fitted in each of holes 3074 and 3076. Each of locking pins 3078 is formed of nylon and projects slightly from its associated hole 3074 or 3076 when initially inserted therein as shown in FIG. 18. When adapter 3012 is fully rotated into threaded engagement with plunger 3010 and pony rod 3024, the outward projections of pins 3078 are crushed, flattened and compressed into positions even with abutment surfaces 3048 and 3050. In a compressed state, pins 3078 exert outward pressure on the outer end of plunger 3010 and the inner end of pony rod 3024 thereby inhibiting their unintended rotation, locking adapter 3012 to plunger 3010 and pony rod 3024.

Pony rod 3024 includes an elongated, cylindrical body 3080 adapted for reciprocation into, and out of, power end 3026. A helically threaded bore 3072 is provided in the inner end of body 3080 for threaded engagement with adapter 3012. An enlarged bore 3082 is provided in the outer end of body 3080 for reducing the reciprocating weight of pony rod 3024. A peripheral flange 3084 extends outwardly from the outer end of body 3080 and is integrally formed with body 3080. Flange 3084 is provided with a number of holes 3086 through which threaded fasteners (not shown) are extended to connect pony rod 3024 to the drive mechanism within power end 3026.

As was noted above, the reciprocating motion of plunger 3010 within pumping chamber 3014 controls the fluid pressure therein. Suction valve 3020 and discharge valve 3018 respond accordingly to dispense pressurized fluid from chamber 3014, and eventually out of fluid end 3016, at high pressure. The discharged fluid is, then, replaced with fluid from suction valve 3020. Repeated motion of plunger 3010 against packing elements 3088 that seal the open end 3022 of chamber 3014 often causes plunger 3010 to wear to the point where its replacement is necessary.

To replace plunger 3010, the user must perform a few simple steps. First, the power end 3026 of the pump is de-energized and, by suitable movement of the drive mechanism, adapter 3012 is positioned between the stay rods 3090 that connect the power end 3026 to the fluid end 3016. With adapter 3012 preferably located as close to power end 3026 as possible (requiring leftward movement of adapter 3012 from its starting position shown in FIG. 17), a lever is inserted into a suitable one of apertures 3052, 3054 or 3056. Now, access plug 3092, providing an entryway into chamber 3014 and being axially aligned with socket 3038, is unscrewed from fluid end 3016, and a square-ended, plunger key is inserted through the entryway into socket 3038 in plunger 3010. Next, while holding the plunger key as still as possible, adapter 3012 is rotated by means of the lever so as to simultaneously unscrew adapter 3012 from both plunger 3010 and pony rod 3024. Then, by suitable manipulation, adapter 3012 and plunger 3010 are removed from fluid end 3016. By substituting a new plunger 3010 for the old one and reversing the process steps noted above, the new plunger 3010 is made ready for operation in fluid end 3016. The entire event requires just a few minutes to complete.

It should be noted that although one plunger 3010 is shown in the Figures, in embodiments where fluid end 3016 has a triplex arrangement, the associated pump has three plungers 3010 with the same or similar configurations. Similarly, with a quintiplex arrangement, there are four plungers 3010. So, the number of plungers 3010 employed in a pump is variable as is the amount of time required for replacing the worn plungers 3010 of a pump. Regardless, the time required is far less than has been possible with any known plunger designs.

While plunger 3010, pony rod adapter 3012, and pony rod 3024, comprising the plunger assembly, have been described in great detail, it will be appreciated by individuals having knowledge of plunger-type pumps that modifications can be made to plunger 3010, adapter 3012, and pony rod 3024. For example, FIG. 26 shows an alternate plunger 3094. Plunger 3094 has an elongated, cylindrical body 3096 adapted for reciprocation within chamber 3014. An enlarged bore 3098 is provided in the outer end of body 3096. Bore 3098 has a helically threaded, outer portion 3100 for threaded engagement with adapter 3012 and a non-threaded, inner portion 3102 for reducing the reciprocating weight of body 3096. Plunger 3094 has no socket like the one shown at 3038, but rather is provided with twelve, radial holes 3104 penetrating body 3096 around outer portion 3100. Holes 3104 permit plunger 3094 to be grasped by a spanner wrench (not shown) extended between stay rods as shown at 3090 during the installation or removal of plunger 3094. Therefore, it must be understood that these embodiments are not limited solely to plunger 3010 and adapter 3012, but encompasses any, and all, plungers and pony rod adapters within the scope of the description.

Referring now also to FIGS. 29-37 in the drawings, an alternative embodiment to the plunger assembly of FIGS. 11-14 and 17 is illustrated. The numerical identifiers referenced in this section will refer to FIGS. 29-37 and to FIGS. 11-14. This plunger assembly includes a dove-tail clamp assembly 201 in operation with the pony rod and plunger. In particular, clamp assembly 201 is an alternative embodiment of pony rod adapter 126, 526. Clamp assembly 201 is able to operate with assemblies 410 and 10 and any other fluid end assembly as described previously. Clamp assembly 201 is configured to operate similarly to that of pony rod adapters 126, 526 in that clamp assembly 201 couples plunger 16 and pony rod 128 together, so as to permit power end 34 to drive plunger 16 within pump housing 12. Plunger 16 and pony rod 128, as well as the other portions of assemblies 10 and 410, maintain the same form and function as was described previously. Clamp assembly 201 includes a clamp 203, 215 having two symmetric half portions, and a clamp adapter stud 205. FIG. 29 illustrates a perspective view of one embodiment of clamp assembly 201 coupled to plunger 16 and pony rod 128. Clamp assembly 201 in FIG. 29 is illustrated without the use of a deflector 204, seen in FIG. 32. The purpose and function of deflector 204 within clamp assembly 201 will be described below.

Pump housing 12 is a steel block adapted for attachment to the power end of a high-pressure pump 34 by a number of stay rods 36. Stay rods 36 maintain the relative distance between pump 34 and housing 12. Conventional fluid ends have typically provided an aperture in the pump housing, opposite the power end, that permits plunger 16 to be removed from the assembly by passing through the fluid end, away from the power end. With fluid ends 10 and 410, the suction valves and discharge valves are aligned such that the aperture is not available. Therefore, removal of plunger 16 occurs in the present application by translating plunger 16 toward pump 34. The space between pump 34 and fluid end 10, 410 is fixed. It is understood that plungers 16 may be modified in length and diameter to accommodate removal from the fluid end.

Referring in particular to FIG. 30, a partial section view of plunger 16 and pony rod 128 is illustrated. Clamp assembly 201 is configured to operate with conventional plungers and pony rods of various fluid end assemblies. As noted previously, pony rod 128 includes a helically threaded bore 146 on the second inner end. Likewise, plunger 16 includes a helically threaded bore 140 on a first end. Pony rod adapter 126, 526 threadedly coupled to each part through corresponding helically threaded bores 140, 146.

Pony rod 128 has an abutment surface 208 relatively perpendicular to centerline A, located at the second inner end. Similarly, plunger 16 has an abutment surface 210 located in the first outer end, oriented relatively perpendicular to centerline A.

Referring in particular to FIG. 31, clamp assembly 201 further includes clamp adapter studs 205 configured to threadedly engage respective helically threaded bores 140, 146 in place of pins 134, 136 of pony rod adapter 126. Stud 205 includes a threaded portion 207 a, a seat portion 207 b, and a flange portion 207 c. Studs 205 are sized in diameter and threaded to engage bores 140, 146 of varied sizes. In so doing, clamp assembly 201 is configured to function as a retrofit to existing conventional fluid end systems. It is understood that all members of clamp assembly 201 may be sized differently to accommodate a range of fluid end assemblies and power ends.

Threaded portion 207 a includes threads for engaging bore 140, 146. Stud 205 has a central axis 206 that is coaxial with centerline A when in threaded engagement with bores 140, 146. Seat portion 207 b is adjacent thread portion 207 a. The outer surface of seat portion 207 b is relatively smooth for mating with plunger 16 or pony rod 128. Seat portion 207 b is recessed within plunger 16 or pony rod 128 when stud 205 is secured by interference fit via thread portion 207 a. Flange portion 207 c is adjacent seat portion 207 b. Flange portion 207 c includes a flange 211 and a groove 213. Groove 213 is formed by the contour of the flange surface as flange 211 extends externally away from seat potion 207 b, away from central axis 206. Flange 211 extends radially around central axis 206 forming the relatively bulbous flange shape. When stud 205 is engaged in bores 140, 146, stud 205 is configured to extend away from abutment surfaces 208 and/or 210. In this embodiment, flange 211 extends over abutment surfaces 208 and/or 210 so as to form groove 213. Clamp 203 is configured to contact the groove surface between flange 211 and abutment surface 208 and/or 210 in a non-threaded relationship with studs 205. As discussed later, by engaging the groove surface, clamp 203 couples plunger 16 and pony rod 128 together without concern for debris-filled threads and the need to constantly tighten connections.

Although flange 211 has been described having a radially extending bulbous shape, it is understood that other shapes are possible. Furthermore, other embodiments may have one or more flanges or ribbed surfaces permitting engagement of clamp 203. The present application conceives of the use of one or more flanges 211 or ribs protruding from abutment surface 208/210 for clamp 203 to clamp around.

A setting aperture 214 is formed within flange portion 207 c relatively perpendicular to a flange face 216. Aperture 214 is set within flange 211 a set distance. Setting aperture 214 has an axis 218. Axis 218 is offset from and parallel with central axis 206. Setting aperture 214 is configured to permit stud 205 to be tightened and loosened within bores 140, 146. Although described as extending within flange portion 207 c, it is understood that aperture 214 may extend any distance within stud 205.

Stud 205 also includes a stud bore 237. Stud bore 237 is an aperture formed within stud 205 similar to that of aperture 214. Bore 237 extends internally within stud 205 from flange face 216. Bore 237 is coaxially aligned with central axis 206. To threadedly engage stud 205 within bores 140, 146, a setting tool (not shown) is inserted into both a stud bore 237 and setting aperture 214 and rotated, so as to apply a torque in either a clockwise or counterclockwise direction about central axis 206. Rotation of stud 205 engages or releases threaded portion 207 a from bores 140, 146.

Referring now also to FIGS. 32 and 33 in the drawings, a clamp 215 is illustrated. Clamp 215 is another embodiment of clamp 203. Clamp 203 and 215 operate in a similar form and function except that clamp 215 is illustrated as having deflector 204 integral within each portion. Description of the functions and form of clamp 215 will apply equally to that of clamp 203 except with regard to deflector 204.

Clamp 215 has a first portion 215 a and a second portion 215 b. A central axis 217 extends along the center of clamp 215 coaxial with a central bore 219. Central axis 217 is configured to coaxially align with centerline A when clamp 215 is secured around studs 205. Clamp 215 includes a plunger end 226 and a pony rod end 228. A cavity 224 is formed in each end 226, 228 of clamp 215. Cavity 224 is formed internally within clamp 215 and includes a cavity face 230. Cavity 224 is configured to accept flange portion 207 c of studs 205. When assembled, clamp 215 surrounds flange portion 207 c, thereby coupling plunger 16 and pony rod 128 together. Furthermore, when clamp 215 is assembled, clamp 215 operates to conceal internal components of clamp assembly 201, namely stud 205 and an alignment pin 231 (see FIG. 34).Clamp 215 is fastened together by use of one or more fasteners (not shown) through a fastener aperture 225.

It is understood that each portion 215 a and 216 b include some of the same features of clamp 215 as a whole. When describing features of clamp 215 with respect to each portion 215 a and 215 b, the respective reference letters “a” and “b” will be used to denote the features as seen on each portion 215 a and 215 b respectively.

Each portion 215 a and 215 b have a mating surface 227 a, 227 b that defines a plane running parallel with centerline A and/or axis 217. First portion 215 a and second portion 215 b contact one another along each mating surface 227 a, 227 b. Clamp 215 is symmetric about the plane defined by the mating surfaces. Being that first portion 215 a and second portion 215 b are symmetric about mating surface 227, discussion will be given concerning the features and functions of first portion 215 a with the understanding that second portion 215 b will have the same features and functions. It is also understood that the features and functions of clamp 215 apply equally to that of clamp 203.

Each portion 215 a, 215 b included half of cavity 224, lip 223 and recess 221 at both end 226, 228. Cavity 224 a extends from mating surface 227 a, radially outward from axis 217. Pony rod end 228 has an exterior face 229 and plunger end 226 has a exterior face 222. Exterior faces 229 a, 229 b wrap around and fold over both cavities 224 a so as to form lip 223 a at each end 226, 228. Cavity 224 a is defined as the area bound by a cavity face 230 a and a plane defined by the exterior faces. A recess 221 a is formed within cavity 224 a, being defined by the area between lip 223 a and cavity face 230 a.

In operation, plunger 16 and pony rod 128 are spaced apart a designated distance. The distance, as measured between flanges 211 of studs 205 within plunger 16 and pony rod 128, coincides with the distance between recesses 221 on opposing ends of each clamp portion 215 a, 215 b. Mating surface 227 a, 227 b of each clamp portion 215 a, 215 b are brought into contact. When in contact, flange 211 is engaged within recess 221 and groove 213 receives lip 223 for studs 205 associated with plunger 16 and pony rod 128 (non-threaded relationship). Fasteners are inserted into apertures 225 to couple clamp portions 215 a and 215 b together. Threaded fasteners are preferably used but other types of fasteners are possible. Although portion 215 a was described above, the same form and features are associated with respect to portion 215 b due to the symmetric nature of clamp 215.

While clamp 215 is installed about studs 205, exterior face 229, 222 is adjacent abutment surfaces 208, 210 respectively. Exterior faces 229, 222 are configured to permit a small gap of space between it and each abutment surfaces 208, 210. This avoids issues with binding and assists in permitting easier removal of clamp 215, 203.

Referring now also to FIG. 34 in the drawings, an alignment pin 231 is illustrated. During installation of clamp 215, 203, each clamp portion 215 a, 215 b is to be aligned with respect to centerline A. Clamp assembly 201 may include the use of alignment pin 231. Alignment pin 231 is configured to serve as an optional tool to assist in the alignment of each clamp portion 215 a, 215 b with respect to each stud 205. Alignment pin 231 has a center portion 233 of cylindrical shape and opposing end portions 235 a and 235 b integrally coupled to center portion 233. End portion 235 a is inserted into stud bores 237 located respectively within stud 205 used with pony rod 128 and plunger 16. Central bore 219 is configured to contact the outer surface of center portion 233. Center portion 233 and each end portion is coaxially aligned with centerline A. It is understood that alignment pin 231 is optionally used with clamp assembly 201.

Referring now also to FIG. 35 in the drawings, a cross sectional view of studs 205 set within plunger 16 and pony rod 128. Studs 205 are included within clamp assembly 201 to allow for retrofit capabilities with plungers and pony rods having threaded bores 140, 146.

Referring now also to FIGS. 36 and 37 in the drawings, an alternative embodiment of clamp assembly 201 is illustrated. Clamp assembly 240 is an alternate embodiment of clamp assembly 201 and includes similar forms and functions to that of assembly 201 except as described herein. Clamp assembly 240 includes a plunger 241, a pony rod 243, and clamps 203, 215. Assembly 240 continues to include the use of clamps 203 or 215. However, in assembly 240, studs 205 are removed and a flange portion 245 is integrally formed into the abutment surfaces of plunger 16 and pony rod 128, thereby forming plunger 245 and pony rod 243. The form and functions of plunger 241 and pony rod 243 are similar to those described previously with respect to assembly 201.

Flange portions 245 extend from an abutment surface 246 a of plunger 241 and abutment surface 246 b of pony rod 243. Each flange portion 245 includes a respective flange and groove similar in form and function to that of stud 205. In such an embodiment, no setting aperture 214 is required due to the integral nature of flange portion 245. A stud bore 247 is located within plunger 241 and pony rod 243, having similar form and function to that of stud bore 237. Stud bore 247 is configured to optionally accept the use of alignment pin 231 when used.

Clamp assembly 201 is depicted in FIG. 29 without the use of a deflector 204. In FIG. 32, clamp portions 215 a and 215 b are shown as having integrally formed deflectors 204. Clamp assembly 201 optionally includes a deflector 204. Deflector 204 may be integrally formed with clamp assembly 201, as seen with clamp 215; or may be a separate member of clamp assembly 201, as seen with clamp 203. Deflector 204 is typically located adjacent the intersection of clamp 215, 203 and pony rod 128, 243. To aid in the removal of plunger 16, 241, the length of plunger 16, 241 is typically minimized as much as possible as a result of having to be removed between the fluid end and power end. In so doing, clamp assembly 201 and/or pony rod adapter 126, 526 are configured to translate within fluid end assembly 10 as pony rod 128 cycles between an extended and retracted position. To avoid contact between deflector 204 and pump housing 12, deflector 204 is located more toward pony rod 128, 243. Other locations may be used depending on whether deflector 204 is integral with clamp 215, 203 or a separate member.

Seals around rotatable gland nut 46 are susceptible to failure over time. When the seals fail, a pressurized stream of fluid can escape from pumping chamber 18 and cause damage to pump 34 or other members. Deflector 204 is configured to include an angled surface 247 to deflect any streams of escaped fluid. Deflector 204 thereby is used as a sacrificial part, adapted to receive the fluid stream as opposed to pump 34. Deflector 204 is easier to replace and has a drastically reduced price compared to pump 34. An additional feature of deflector 204 is that the pressurized stream of fluid is deflected away from centerline A at some angle thereby making the stream more easily detected to operators. Once detected, gland nut 46 can be repaired prior to any significant damage occurring.

The plunger assemblies described with respect to FIGS. 17-37 are configured to reduce and correct the improper and laborious maintenance of a pump system by improving access and simplifying the configurations. Additionally, the plunger assemblies of FIGS. 17-37 are configured to reduce and correct the improper operation of the pump system.

Valves and Seal Inserts

Referring now to FIGS. 38-40 in the drawings, an alternative embodiment of a suction valve is illustrated. Suction valve 5010 is similar in form and function to suction valves 20 and 420 described in FIGS. 12C and 13C respectively. Suction valve 5010 is configured to minimize the likelihood of proppant being knocked out of suspension. Suction valve 5010 permits fracture fluids with higher than normal concentrations of suspended proppants to be pumped with substantial cost savings accruing to the user. Suction valve 5010 can be seated in a shallow suction passage in a fluid end, thereby resulting in less metal to be removed from the body of the fluid end at the time of manufacture. Additionally, suction valve 5010 is configured to be lightweight in construction, inexpensive to manufacture, and dependable in use.

Suction valve 5010 includes a valve seat and guide assembly 5012 for positioning in a suction passage 5014 of a fluid end 5016 and a piston 5018 that moves within assembly 5012 to control the flow of fluid through passage 5014. Piston 5018 has a head 5020 for engaging the seat portion 5022 of assembly 5012 and a stem 5024 extending downwardly from head 5020 through the guide portion 5026 of assembly 5012. A valve keeper 5028 is fitted upon the bottom of stem 5024 and is retained there by a split ring 5030. A compressed spring 5032 is positioned between guide portion 5026 and keeper 5028 for normally retaining head 5020 in engagement with seat portion 5022 to prevent fluid flow through passage 5014. A valve retainer 5034 is screwed into suction passage 5014 to retain the balance of valve 5010 within fluid end 5016 and provide for the attachment of valve 5010 to a suction manifold (not shown).

Seat portion 5022 comprises an outer ring 5036 that fits snugly within the narrowed, unthreaded, upper part 5014 u of passage 5014. The height of outer ring 5036 is sufficient to place the top of the top surface 5038 thereof flush with the sides of a pumping chamber 5040 in fluid end 5016. Seat portion 5022 also includes a peripheral flange 5042 that is integrally formed with outer ring 5036 and projects outwardly from the bottom of outer ring 5036 so as to rest upon a shoulder or seat deck 5044 where the wide, internally threaded, lower part 5141 of passage 5014 meets upper part 5014 u.

Outer ring 5036 has an outer surface 5046 that slopes upwardly an inwardly at a shallow angle corresponding in slope with upper part 5014 u of passage 5014. A number of peripheral channels 5048, 5050, and 5052 are provided around outer surface 5046 at spaced-apart intervals. Within channels 5048, 5050 and 5052 are positioned o-ring seals 5054, 5056 and 5059, respectively. Tapering outer surface 5046, as described, prolongs the life of seals 5054 and 5056 as well as reduces the likelihood of fatigue cracks forming in fluid end 5016, a problem encountered in “old style” fluid ends where valve seats pressed outwardly on the sides of pumping chambers during pressurizing plunger strokes.

Outer ring 5036 has an inner surface 5058 that is shaped to reduce turbulence in fluid moving through valve 5010. Inner surface 5058 has a top part 5058 t that is beveled such that it slopes downwardly and inwardly toward the center of seat portion 5022 at an angle of about 36°, an angle that can be increased as a matter of design choice to optimize the action of valve 5010. Inner surface 5058 also has a bottom part 5058 b that slopes upwardly and inwardly at a steeper incline, say 74°. Connecting bottom part 5058 b and top part 5058 t together, inner surface 5058 has a medial part 5058 m that slopes upwardly and inwardly at an inclination that is about 10° less than that of bottom part 5058 b. Thus, inner surface 58 is “stepped” to funnel fluids through a narrowed neck 5060 in seat portion 5022 at the junction of the top part 5058 t and medial part 5058 m with minimal pressure losses.

Peripheral flange 5042 extends outwardly from the bottom of outer ring 5036 at right angles. The top of flange 5042 snugly engages seat deck 5044 thereby ensuring a strong platform for assembly 5012. To ensure against fluid leaks around seat deck 5044, the bottom of flange 5042 is provided with a peripheral groove 5062 that receives an o-ring seal 5064 for engaging valve retainer 5034.

Guide portion 5026 includes an inner ring 5066 that slidably receives stem 5024 of piston 5018. Inner ring 5066 has an interior wall 5068 for engaging stem 5024 and an opposed exterior wall 5070. Exterior wall 5070 has an upper part 5070 u and a lower part 5070 l of smaller diameter and substantially equal height. A shoulder 5072 is provided at the junction of the upper and lower parts 5070 u and 5070 l that serves as an abutment for the top of spring 5032. Upper part 5070 u is positioned within seat portion 5022 adjacent flange 5042 and tapers upwardly and inwardly so as to reduce turbulence in a fluid flowing through guide portion 5026. Lower part 5070 l projects outwardly from the bottom of seat portion 5022.

Inner ring 5066 and outer ring 5036 are connected together by three, vertically oriented fins 5074. Fins 5074 radiate outwardly from upper part 5070 u of exterior wall 5070 of inner ring 5066 at 120° intervals to join bottom part 5058 b of outer ring 5036. Fins 5074 are taller than they are wide to best withstand axial loads. Also, fins 5074 are horizontally oriented for minimum weight and maximum strength. Rings 5066 and 5036 and fins 5074 present minimal impediments to fluid flow through assembly 5012 and permit valve 5010 to handle fluids with higher proppant concentrations than normal.

The top of head 5020 is provided with a shallow recess 5076 such that it resembles a bowl. Recess 5076 reduces the mass of piston 5018 thereby permitting piston 5018 to reciprocate at greater speeds and minimize the leakage of fluids through valve 5010. Furthermore, recess 5076 serves to admit the free end of a reciprocating plunger (not shown) within fluid end 5016 so as to allow the length and volume of pumping chamber 5040 to be minimized.

Head 5020 has a beveled, peripheral edge 5078 that is adapted to snugly engage top part 5058 t of seat portion 5022. Extending around edge 5078 is an insert 5080, formed of a durable material, which serves as sealing element for valve 5010. Insert 5080 has a back edge 5082 that is circular in cross section so as to “snap fit” into a correspondingly shaped recess 5084 around head 5020. Back edge 5082 is easy to press into head 5020 at the time of manufacture and has little tendency to loosen during use.

Stem 5024 has a spherical knob 5086 at its bottom end. As shown, the diameter of knob 5086 is smaller than the diameter of stem 5024 to easily fit through inner ring 5066. Knob 5086 is employed to grip piston 5018 during valve servicing operations.

Above knob 5086, stem 5024 is provided with a peripheral groove 5088. Groove 5088 has a top surface 5088 t, a bottom surface 5088 b, and a medial surface 5088 m that connects top surface 5088 t and bottom surface 5088 b together. Top surface 5088 t slopes outwardly and downwardly at an angle of 5° so as to positively grip correspondingly shaped split ring 5030 and keep split ring 5030 from springing outwards during use of valve 5010. Bottom surface 5088 b is horizontally oriented and medial surface 5088 m is vertically oriented to permit the easy installation of split ring 5030.

Valve keeper 5028 is fitted over the bottom of stem 5024 and has a conical configuration. Keeper 5028 has an exterior diameter that increases gradually from its top, where it has the same diameter as exterior wall 5070 l of inner ring 5066, to its bottom. Extending outwardly from the bottom of keeper 5028 is a peripheral rim 5090 that serves as an abutment for the bottom of spring 5032.

A recess 5092 is provided in the bottom of keeper 5028 for snugly receiving split ring 5030 that is fitted into groove 5088 in stem 5024. To ensure that split ring 5030 does not slide from recess 5092, split ring 5030 is provided with a peripheral groove 5094 at its midpoint into which is fitted an o-ring 5096. O-ring 5096 serves as a safety feature to wedge valve keeper 5028 and split ring 5030 together even if spring 5032 breaks thereby reducing the likelihood that piston 5018 will come altogether loose during the use of valve 5010.

Valve retainer 5034 is segmented, hollow, and cylindrical. The upper segment 5034 u of retainer 5034 is provided with external, helical threads 5098 that screw tightly into correspondingly machined threads around lower part 5141 of passage 5014.

Valve retainer 5034 has a middle segment 5034 m that is integrally formed at the bottom of upper segment 5034 u. As shown, middle segment 5034 m has a polygonal cross section with six, principal, external faces 5100 separated by six, secondary, external faces 5102 hexagonally arranged. Faces 5100 can be gripped by a wrench for rotating valve retainer 5034 to unscrew threads 5098 from those of passage 5014 during the installing and servicing of valve 5010.

Valve retainer 5034 has a bottom segment 5034 b that is integrally formed at the bottom of middle segment 5034 m. Bottom segment 5034 b is circular in cross section and has a peripheral slot 5104 around the middle thereof. Slot 5104 accommodates a VICTAULIC coupling (not shown) for the quick and easy connection of valve retainer 5034 to a suction manifold that delivers fluid to valve 5010.

Valve retainer 5034 has a segmented passageway 5106 that conveys fluid through segments 5034 u, 5034 m, and 5034 b into assembly 5012. The uppermost fraction of passageway 5106 extends downwardly from the top of upper segment 5034 u and acts as a recess for snugly receiving flange 5042 of assembly 5012. The uppermost fraction of passageway 5106 is defined by a circular, side wall 5108 that closely accommodates the periphery of flange 5042 and a flat, top wall 5110 that projects inwardly from side wall 5108 to engage the bottom of flange 5042. A middle fraction of passageway 5106 provides an annular flow space around valve keeper 5028 below the uppermost fraction. The middle fraction, thus, bulges around valve keeper 5028 with a cascade of five walls 5112-5120. First wall 5112 extends vertically downward from the inner edge of top wall 5110. Second wall 5114 slopes downwardly and outwardly from the bottom of first wall 5112. Third wall 5116 extends vertically downward from the bottom of second wall 5114. Fourth wall 5118 slopes downwardly and inwardly from the bottom of third wall 5116. Fifth wall 5120 extends vertically downward from the bottom of fourth wall 5118. (Fifth wall 5120, being small in diameter and near the fluid entry into valve 5010, is a narrowed neck that limits the amount of fluid entering valve 5010 and increases the velocity of that fluid. By properly sizing the diameter of wall 5120, a user of valve 5010 can establish a jetting action for fluids passing through valve 5010 that drives any proppant that may collect in, or around, keeper 5028 into the flow stream and from valve 5010). The lowermost fraction of passageway 5106 is defined by a tapered, bottom wall 5122 that slopes upwardly and inwardly from the bottom of bottom segment 5034 b and joins, at its top, the bottom of fifth wall 5120.

The assembly, installation, and use of valve 5010 are straightforward. To assemble valve 5010, insert 5080 is first positioned in recess 5084 in piston 5020. Then, stem 5024 is extended through inner ring 5066 of assembly 5012. Next, spring 5032, keeper 5028, and split ring 5030 (with o-ring 5096 attached) are, in turn, positioned over stem 5024. Now, by compressing spring 5032 against shoulder 5072 of inner ring 5066 with keeper 5028, split ring 5030 is worked into peripheral groove 5088. Afterward, the assembled portion of valve 5010 is slid into the upper portion 5014 u of passage 5014 in fluid end 5016. At this point, valve keeper 5028 is screwed into lower portion 5141 of passage 5014 by means of a wrench gripping external faces 5100 of valve retainer 5034. Finally, VICTAULIC clamps (not shown) are employed to connect valve 5010 at slot 5104 to a suction manifold associated with fluid end 5016. Valve 5010 is ready for use after a few minutes work.

After installation of valve 5010 in fluid end 5016, a plunger (not shown) is reciprocated above head 5020. As the plunger moves forward to drive fluid from its cylinder, peripheral edge 5078 of head 5020 is snugly pressed under the influence of spring 5032 against top surface 5058 t of seat portion 5022 ensuring that no fluid leaks through passage 5014. When the plunger travels back to its starting point, a partial vacuum is created that lifts piston 5018 against the compressive force of spring 5032 and draws fluid upwardly through passageway 5106 and valve 5010. The process of opening and closing valve 5010 is entirely automatic and requires mere fractions of a second to accomplish. Since the valve 5010 minimizes turbulent flow, proppant is not captured by valve 5010 to block flow through assembly 5012 or retainer 5034 under normal conditions of use.

While suction valve 5010 has been described with a high degree of particularity, it will be appreciated by those skilled in the art that modifications can be made to it. Therefore, it is to be understood that valve 5010 encompasses any and all valve embodiments within the scope of the present application.

Referring now to FIGS. 41 and 42 in the drawings, an alternative embodiment of a discharge valve is illustrated. Discharge valve 6010 features a valve seat and a valve guide disposed above the valve seat. The valve guide has a discharge passage plug and a guide rod that is affixed to, and projects downwardly from, the bottom of the plug. The valve guide also has an interiorly threaded, lifting sleeve that is affixed to, and projects upwardly from, the top of the plug. A piston is disposed between the valve seat and the valve guide. The piston has a head portion for engaging the top of the valve seat, and a stem portion that is affixed to, and extends upwardly from, the head portion. The stem portion has a longitudinal socket within which the guide rod is slidably received. The stem portion also has a number of apertures that intersect the socket for providing pressure relief to the socket. A compressed spring is disposed between the valve guide and the head portion of the piston for normally retaining the head portion in engagement with the valve seat. An externally threaded, valve retainer is disposed above the valve guide for pressing the valve guide toward the valve seat.

Discharge valve 6010 is configured to reduce the likelihood of proppant blockages by offering few impediments to fluid flow so that fracturing fluids can flow through it with minimum turbulence. As a result, fracturing fluids with higher than normal concentrations of suspended proppants can be pumped. Furthermore, discharge valve 6010 can be seated in a shallow pocket in a fluid end of a pump. A shallow pocket requires that less load-bearing material be removed from the fluid end at the time of its manufacture thereby increasing the strength and durability of a fluid end. It is less likely, then, that a fluid end configured to receive discharge valve 6010 will fail from the development of stress cracks.

Discharge valve 6010 features a “male” valve guide upon which a piston rides. The valve guide carries the piston to a valve seat so as to close the discharge valve with great precision and minimal wobble that, if present, could induce vibrations in the pump within which the discharge valve is mounted. Additionally, discharge valve 6010 features a ported piston that permits the piston to slide freely on the valve guide and reduces the likelihood that discharge valve 6010 will become stuck “open” or “closed” so as to permit valve leakage. Discharge valve is configured to remain lightweight in construction, inexpensive to manufacture, and fully dependable in use.

Discharge valve 6010 includes a valve seat 6012 for positioning in the bottom of a discharge passage 6014 of a fluid end 6016 and a reciprocating piston 6018 for controlling the flow of fluid through passage 6014. Piston 6018 has a head portion 6020 for engaging valve seat 6012 and a hollow, stem portion 6024 extending upwardly from head portion 6020. A valve guide 6026 is positioned above piston 6018 in passage 6014 and has a guide rod 6028 that projects downwardly into a longitudinal socket 6030 provided in stem portion 6024 where it is slidably received. A number of radial apertures 6032 penetrate the bottom of stem portion 6024 equalize pressures between passage 6014 and socket 6030. A compressed spring 6034 is disposed between the valve guide 6026 and head portion 6020 to normally press head portion 6020 into engagement with seat 6012. A valve retainer 6036 is screwed into the top of passage 6014 to retain valve 6010 within fluid end 6016.

Valve seat 6012 is a hollow cylinder with an inner wall 6038 that is shaped to minimize turbulent flow. Wall 6038 has a top part 6038 t that slopes downwardly and inwardly toward the center of seat 6012 at an angle of about 36°. Wall 6038 also has a bottom part 6038 b that slopes upwardly and inwardly at an incline that is substantially equal to that of top part 6038 t. Finally, wall 6038 has a substantially vertical, middle part 6038 m that connects the bottom of top part 6038 t to the top of bottom part 6038 b.

Valve seat 6012 has an outer wall 6040 that snugly engages the sides of passage 6014. Outer wall 6040 slopes downwardly an inwardly at a shallow angle corresponding in slope with a taper provided in the bottom of passage 6014. A pair of peripheral channels 6042, 6044 is provided around the middle of wall 6040. Within each of channels 6042, 6044 is positioned an o-ring seal 6046, 6048 to inhibit leaks around seat 6012. Sloping wall 6040, as described, prolongs the life of seals 6046, 6048 and reduces the likelihood of fatigue cracks forming in fluid end 6016.

Projecting from the top of outer wall 6040 is a peripheral flange 6050. The bottom of flange 6050 slopes downwardly and inwardly toward outer wall 6040 at an angle of about 30°. This 30° angle corresponds with that of a seat deck 6052 formed at the junction of the small-diameter, bottom portion 6014 b of passage 6014 and the medium-diameter, middle portion 6014 m of passage 6014. A sloping seat deck 6052, as described, has been found to provide a strong platform for seat 6012 that minimizes induced stresses in fluid end 6016.

Head portion 6020 includes a bottom part 6020 b and a rim part 6020 r that extends upwardly and outwardly from the periphery of bottom part 6020 b. Bottom part 6020 b is conical with a rounded bottom wall 6054 and a side wall 6056 that extends upwardly and outwardly from bottom wall 6054 at a slope of about 60°. Rim part 6020 r, however, has a side wall 6058 that projects upwardly and outwardly from the top of side wall 6058 at an angle of about 36° so as to permit flush positioning of rim part 6020 r against top part 6038 t of seat 6012. In use, bottom part 6020 b projects sharply into the flow of fluid passing through seat 6012 to initiate a radial deflection of the fluid around piston 6018 that keeps piston 6018 centered on guide rod 6028. Centering piston 6018 keeps piston 6018 from sticking on guide rod 6028 and ensures that rim part 6020 r seats perfectly against seat 6012, inhibiting leaks.

Rim part 6020 r projects above bottom part 6020 b so as to define a circular recess 6060 in the top of head portion 6020. Recess 6060 reduces the weight of piston 6018 so that piston 6018 can reciprocate more rapidly than it could without it. Recess 6060 further serves as an abutment for the bottom of spring 6034.

Stem portion 6024 extends upwardly from the center of recess 6060 within spring 6034. Stem portion 6024 is integrally formed with head portion 6020 and has an exterior diameter that decreases gradually from its bottom within recess 6060 to its top positioned above rim part 6020 r. The top of stem portion 6024 abuts valve guide 6026 to define the upper limit of travel of piston 6018. Socket 6030 extends downwardly through the center of stem portion 6024 and into the center of rim part 6020 r. The bottom of stem portion 6024 has a peripheral, downwardly and outwardly sloping ledge 6062 that provides a surface through which apertures 6032 can penetrate to enter the inner/bottom end of socket 6030 and acts to deflect the bottom of spring 6034 away from apertures 6032 that might otherwise block apertures 6032. Piston 6018 has apertures 6032 that extend outwardly from socket 6030 at intervals of 60°. If one or several apertures 6032 become blocked, the remainder serve as backups to balance the pressure within socket 6030 with that in passage 6014.

Side wall 6058 of rim part 6020 r is provided with a peripheral recess 6064 that snugly receives an insert 6066, formed of a durable material, serving as a principal, sealing element for valve 6010. Recess 6064 has a back edge 6068, remote from side wall 6058, that is circular in cross section. Insert 6066 has a back edge 6070 that is corresponding in shape to that of back edge 6068 so as to “snap fit” into recess 6064. At the time of manufacture, back edge 6070 is easy to press into head portion 6020 and has little tendency to loosen over time.

Valve guide 6026 includes a circular plug 6072 having a circular, vertical, side wall 6074 and a circumferential flange 6076 projecting outwardly from the top of side wall 6074. Flange 6076 engages a seat deck 6078 in fluid end 6016 at the junction of the medium-diameter, middle portion 6014 m of passage 6014 and the large-diameter, helically threaded, top portion 6014 t of passage 6014. Since guide 6026 transmits smaller loads to fluid end 6016 than valve seat 6012, it is not necessary that seat deck 6078 be sloped like seat deck 6052. To prevent fluid leaks around plug 6072, side wall 6074 is provided with a pair of peripheral grooves 6080, 6082 beneath flange 6076 within which are positioned o-ring seals 6084, 6086 for engaging fluid end 6016.

Plug 6072 has a circular recess 6088 in the bottom thereof. Recess 6088 is centered on the longitudinal axis of valve 6010. A circular platform 6090 extends downwardly from the center of recess partially toward the bottom of plug 6072. Platform 6090 serves as an abutment for the top of stem portion 6024 of piston 6018. The annular area in recess 6088, formed around platform 6090, acts an abutment for the top of spring 6034.

A cylindrical, guide rod 6028 is integrally formed with plug 6072. Guide rod 6028 is smaller in diameter than platform 6090 and extends downwardly from the center of platform 6090 so as to be slidably received within socket 6030 of stem portion 6024. Guide rod 6028 is long enough to retain stem portion 6024 over the full range of travel of piston 6018 yet is sufficiently short as to avoid contacting the bottom of socket 6030 which could cause damage to both guide rod 6028 and piston 6018.

Projecting from the top of plug 6072 is a cylindrical sleeve 6092 with an interiorly threaded socket 6094. Sleeve 6092 is used in a conventional manner to lift valve guide 6026 from passage 6014 when it is desired to service valve 6010.

Valve retainer 6036 includes a circular cap 6096 having a helically threaded side wall 6098 that permits retainer 6036 to be screwed into top portion 6014 t of passage 6014. To facilitate the turning of retainer 6036, a polygonal pin 6100 of hexagonal cross section is affixed to, and extends upwardly from, the top of cap 6096. Pin 6100 is dimensioned so as to be easily grasped by a wrench. A cylindrical cutout 6102 is provided in the bottom of cap 6096 to loosely receive sleeve 6092 projecting upwardly from the center of plug 6072. When screwed fully into passage 6014, the bottom of cap 6096 presses downwardly upon the top of plug 6072 so as to hold flange 6076 tightly against seat deck 6078.

After installing discharge valve 6010 in passage 6014, a plunger (not shown) is reciprocated in a pumping chamber beneath valve seat 6012. As the plunger moves forward to drive pressurized fluid through seat 6012, the compressive force of spring 6034 is overcome and piston 6018 is elevated to the position shown in FIG. 41. With head portion 6020 being disengaged from seat 6012, fluid flows past seat 6012, bottom part 6020 b serving to guide piston 6018 to a central location in the flow stream, and into middle portion 6014 m of passage 6014. A discharge port (not shown) in fluid end 6016 conveys pressurized fluid from middle portion 6014 m and from fluid end 6016. When the plunger travels back to its starting point, the fluid pressure is reduced within seat 6012 such that the compressive force of spring 6034 drives side wall 6058 and insert 6066 of piston 6018 onto top part 6038 t of seat 6012 thereby preventing substantial volumes of fluid in middle portion 6014 m to travel back into seat 6012 or the pumping chamber of fluid end 6016.

The process of opening and closing discharge valve 6010 is entirely automatic and can be accomplished many times in a second. Since the valve 6010 minimizes turbulent flow, proppant is not “knocked out” by valve 6010 so as to block the flow of fracture fluid through passage 6014. Fluids containing greater proppant loads than normal can be pumped through valve 6010 providing great cost savings to a user.

While discharge valve 6010 has been described with a high degree of particularity, it will be appreciated by those skilled in the art that modifications can be made to it. Therefore, it is to be understood that valve 6010 encompasses any and all valve embodiments within the scope of the present application.

The valves described with respect to FIGS. 38-72 are configured to reduce and correct the improper operation of the pump system.

Referring now to FIGS. 43-50 in the drawings, an alternate embodiment of a valve insert is illustrated. Valve insert 7010 features a ring made of a resilient material like a durable plastic. The ring has a shape that is defined by the rotation of an irregular polygon around a central axis. Superposing a quadrilateral and a circle forms the irregular polygon. Valve insert 7010 is configured for attachment to the movable piston of a suction valve or a discharge valve that does not slide, roll or pivot once installed. Furthermore, valve insert 7010 channels fluid around its exterior surfaces with minimal turbulence and wear from abrasive fluids. As a result, valve insert 7010 has a greater service life than that of any known sealing element.

Valve insert 7010 is configured to be interchangeably used in either a suction valve or a discharge valve thus reducing the inventory of parts that a pump operator must keep on hand for repairs. Furthermore, valve insert 7010 can be easily installed in a valve without specialized tools or prolonged training being required to accomplish the task. This is due to valve insert 7010 being configured to couple to the valves with a “snap fit”, of which a proper fit can be felt, seen, and heard. Valve insert 7010 is lightweight in construction, inexpensive to manufacture, and fully dependable in use.

Valve insert 7010 is a ring, made of a durable plastic or other suitable, resilient material, whose shape is defined by the rotation of an irregular polygon P around a central axis A. The superposing of a quadrilateral Q and a circle C forms polygon P.

Quadrilateral Q is a plane figure having four sides s1, s2, s3, and s4 and four angles a1, a2, a3, and a4. Sides s1 and s3, measuring 0.876 inches and 0.499 inches in length respectively, are arranged parallel to one another. Side s2 is 0.519 inches long and connects sides s1 and s3 together. Side s2 meets side s1 at an angle a1 of 90° and, also, meets side s3 at an angle a2 of 90°. Also, side s4, measuring about 0.641 inches in length, is positioned opposite side s2 and connects sides s1 and s3 together. Side s4 meets side s3 at an angle a3 of about 13.5° and, also, meets side s1 at an angle a4 of about 55°.

Circle C is a closed plane curve consisting of all points equally distant from a point within it, called the center c. The distance from center c to the closed plane curve is the radius r of circle C. Radius r measures about 0.375 inches in length.

When superposed, center c is positioned within the bounds of quadrilateral Q, i.e., the area bounded by sides s1, s2, s3, and s4, with portions of circle C extending beyond the bounds of quadrilateral Q. Quadrilateral Q and circle C touch one another at three points p1, p2, and p3. Circle C crosses side s1 at point p1 at a shallow angle and crosses side s2 at point p2 at another shallow angle. Circle C touches, but does not cross, side s3 at point p3 near the midpoint of side s3.

Polygon P is defined by five line segments l1, l2, l3, l4, and l5. Line segment 11 is a portion of side s1 adjoining side s4 and measuring about 0.279 inches in length. Line segment l2 is an arc of circle C measuring about 1.374 inches in length. Line segment l3 is a portion of side s2 adjoining side s3 measuring about 0.125 inches in length. Line segment l3 and side s3 fully coincide in terms of length and location as do line segment l4 and side s4.

Rotating polygon P around central axis A provides valve insert 7010 with its outer surfaces. One surface arising from the rotation of line segment 7011 is a circular, inside wall 7012 that extends vertically upward from the bottom of valve insert 7010 and opens toward the interior of valve insert 7010. Similarly, the rotation of line segment 7012 around axis A produces a convex, top wall 7014 that projects, at first, upwardly and inwardly from the top of inside wall 7012, then, projects upwardly and outwardly and, finally, arches outwardly and downwardly from its crest. Also, the rotation of line segment 7013 around axis A results in valve insert 7010 being provided with a round, wing wall 7016 that projects horizontally outward from the outer periphery of top wall 7014. Further, rotating line segment 7014 around axis A generates a circular, outside wall 18 that projects downwardly from wing wall 7016 and parallels inside wall 7012. Finally, rotating line segment 1 s around axis A produces a circular, bottom wall 7020 that slopes downwardly and inwardly from the bottom of outside wall 7018 to join the bottom of inside wall 7012.

Discharge valve 7022 includes a valve seat 7024 and a reciprocating piston 7026. Piston 7026 has a head portion 7028 for engaging valve seat 7024 and a hollow, stem portion 30 extending upwardly from head portion 7028. A valve guide 7032 is positioned above piston 7026 and has a guide rod 7034 that projects downwardly into a longitudinal socket 7036 in stem portion 7030. A number of radial apertures 7038 penetrate the bottom of stem portion 7030. A compressed spring 7040 is disposed between the valve guide 7032 and head portion 7028 to normally press head portion 7028 into engagement with seat 7024. A valve retainer 7042 is screwed into a pump (not shown) to retain valve 7022 therein.

Valve seat 7024 is a hollow cylinder with an inner wall 7044. Wall 7044 has a top part 7044 t that slopes downwardly and inwardly toward center of seat 7024. Wall 7044 also has a bottom part 7044 b that slopes upwardly and inwardly. Finally, wall 7044 has a substantially vertical, middle part 7044 m that connects the bottom of top part 7044 t to the top of bottom part 7044 b.

Valve seat 7024 has an outer wall 7046 that snugly engages the pump within which valve 7022 is positioned. Outer wall 7046 slopes downwardly an inwardly at a shallow angle. A pair of peripheral channels 7048, 7050 is provided around the middle of wall 7046. Within each of channels 7048, 7050 is positioned an o-ring seal 7052, 7054. Projecting from the top of outer wall 7046 is a peripheral flange 7056. The bottom of flange 7056 slopes downwardly and inwardly toward outer wall 7046.

Head portion 7028 includes a bottom part 7028 b and a rim part 7028 r that extends upwardly and outwardly from the periphery of bottom part 7028 b. Bottom part 7028 b is conical with a rounded bottom wall 7058 and a side wall 7060 that extends upwardly and outwardly from bottom wall 7058. Rim part 7028 r, however, has a side wall 7062 that projects upwardly and outwardly from the top of side wall 7060 so as to permit flush positioning of rim part 7028 r against top part 7044 t of seat 7024. Rim part 7028 r projects above bottom part 7028 b so as to define a circular recess 7064 in the top of head portion 7028.

Stem portion 7030 extends upwardly from the center of recess 7064 within spring 7040. Stem portion 7030 is integrally formed with head portion 7028 and has an exterior diameter that decreases gradually from its bottom within recess 7064 to its top positioned above rim part 7028 r. The top of stem portion 7030 abuts valve guide 7032. Socket 7036 extends downwardly through the center of stem portion 7030 and into the center of rim part 7028 r. The bottom of stem portion 7030 has a peripheral, downwardly and outwardly sloping ledge 7066. Piston 7026 has apertures 7038 that extend outwardly from socket 7036.

Side wall 7062 of rim part 7028 r is provided with a peripheral recess 7068 that snugly receives a valve insert 7010, serving as a principal, sealing element for valve 7022. Recess 7068 has a back edge 7070, remote from side wall 7062, which is generally circular in cross section. The top wall 7014, flanked by inside wall 7012 and wing wall 7016, correspond in terms of shape to that of back edge 7070 so as to “snap fit” into recess 7068. Insert 7010 is easy to press into head portion 7028 and has little tendency to loosen over time.

Valve guide 7032 includes a circular plug 7072 having a circular, vertical, side wall 7074 and a circumferential flange 7076 projecting outwardly from the top of side wall 7074. To prevent fluid leaks around plug 7072, side wall 7074 is provided with a pair of peripheral grooves 7078, 7080 beneath flange 7076 within which are positioned o-ring seals 7082, 7084.

Plug 7072 has a circular recess 7086 in the bottom thereof. Recess 7086 is centered on the longitudinal axis of valve 7022. A circular platform 7088 extends downwardly from the center of recess partially toward the bottom of plug 7072.

A cylindrical, guide rod 7034 is integrally formed with plug 7072. Guide rod 7034 is smaller in diameter than platform 7088 and extends downwardly from the center of platform 7088 so as to be slidably received within socket 7036 of stem portion 7030.

Projecting from the top of plug 7072 is a cylindrical sleeve 7090 with an interiorly threaded socket 7092. Sleeve 7090 is used in a conventional manner to lift valve guide 7032.

Valve retainer 7042 includes a circular cap 7094 having a helically threaded side wall 7096 that permits retainer 7042 to be screwed into a pump. To facilitate the turning of retainer 7042, a polygonal pin 7098 of hexagonal cross section is affixed to, and extends upwardly from, the top of cap 7094. A cylindrical cutout 7100 is provided in the bottom of cap 7094 to loosely receive sleeve 7090. In use, the bottom of cap 7094 presses downwardly upon the top of plug 7072.

After installing discharge valve 7022 in a pump, a plunger (not shown) is reciprocated in a pumping chamber beneath valve seat 7024. As the plunger moves forward to drive pressurized fluid through seat 7024, the compressive force of spring 7040 is overcome and piston 7026 is elevated to the position shown in FIG. 7. With head portion 7028 being disengaged from seat 7024, fluid flows past seat 7024. A discharge port (not shown) in the pump conveys pressurized fluid from valve 7022. When the plunger travels back to its starting point, the fluid pressure is reduced within seat 7024 such that the compressive force of spring 7040 drives side wall 7062 and insert 7010 onto top part 7044 t of seat 7024 thereby preventing substantial volumes of fluid from traveling back from valve 7022 into the pumping chamber of the pump. The process of opening and closing valve 7022 is automatic and can be accomplished many times a second.

Suction valve 7110 includes a valve seat and guide assembly 7112 for positioning in a pump (not shown) and a piston 7118 that moves within assembly 7112. Piston 7118 has a head 7120 for engaging the seat portion 7122 of assembly 7112 and a stem 7124 extending downwardly from head 7120 through the guide portion 7126 of assembly 7112. A valve keeper 7128 is fitted upon the bottom of stem 7124 and is retained there by a split ring 7130. A compressed spring 7132 is positioned between guide portion 7126 and keeper 7128 for normally retaining head 7120 in engagement with seat portion 7122 to prevent fluid flow through valve 7110. A valve retainer 7134 is screwed into the pump to retain the balance of valve 7110 within the pump and provide for the attachment of valve 7110 to a fluid source.

Seat portion 7122 comprises an outer ring 7136 and an outwardly projecting peripheral flange 7142 that is integrally formed with outer ring 7136. Outer ring 7136 has an outer surface 7146 that slopes upwardly an inwardly at a shallow angle. A number of peripheral channels 7148, 7150, and 7152 are provided around outer surface 7146 at spaced-apart intervals. Within channels 7148, 7150 and 7152 are positioned o-ring seals 7154, 7156 and 7159, respectively. Outer ring 7136 also has an inner surface 7158 that is shaped to reduce turbulence in fluid moving through valve 7110. Inner surface 7158 has a top part 15% that is beveled such that it slopes downwardly and inwardly toward the center of seat portion 7122. Inner surface 7158 also has a bottom part 7158 b that slopes upwardly and inwardly. Connecting bottom part 7158 b and top part 7158 t together, inner surface 7158 has a medial part 7158 m that slopes upwardly and inwardly.

Peripheral flange 7142 extends outwardly from the bottom of outer ring 7136. The top of flange 7142 snugly engages the pump thereby ensuring a strong platform for assembly 7112. To ensure against fluid leaks around valve 7110, the bottom of flange 7142 is provided with a peripheral groove 7162 that receives an o-ring seal 7164 for engaging valve retainer 7134.

Guide portion 7126 includes an inner ring 7166 that slidably receives stem 7124 of piston 7118. Inner ring 7166 has an interior wall 7168 for engaging stem 7124 and an opposed exterior wall 7170. Exterior wall 7170 has an upper part 7170 u and a lower part 7170 l of smaller diameter and substantially equal height. A shoulder 7172 is provided at the junction of the upper and lower parts 7170 u and 7170 l that serves as an abutment for the top of spring 7132. Upper part 7170 u is positioned within seat portion 7122 adjacent flange 7142 and tapers upwardly and inwardly. Lower part 7170 l projects outwardly from the bottom of seat portion 7122.

Inner ring 7166 and outer ring 7136 are connected together by three, vertically oriented fins (not shown). These fins radiate outwardly from upper part 7170 u of exterior wall 7170 of inner ring 7166 to join bottom part 7158 b of outer ring 7136.

Head 7120 has a beveled, peripheral edge 7178 that is adapted to snugly engage top part 7158 t of seat portion 7122. Extending around edge 7178 is a recess 7184 that is generally circular in cross section and is further shaped to snugly receive valve insert 7010 that serves as sealing element for valve 7110. The top wall 7014, flanked by inside wall 7012 and wing wall 7016, correspond in terms of shape to that of recess 7184 so as to “snap fit” into recess 7184. Insert 7010 is easy to press into head portion 7120 and has little tendency to loosen over time.

Stem 7124 has a spherical knob 7186 at its bottom end. The diameter of knob 7186 is smaller than the diameter of stem 7124 to easily fit through inner ring 7166.

Above knob 7186, stem 7124 is provided with a peripheral groove 7188. Groove 7188 is shaped so as to positively grip a correspondingly shaped split ring 7130 and keep split ring 7130 from springing outwards during use of valve 7110.

Valve keeper 7128 is fitted over the bottom of stem 7124 and has a conical configuration. Keeper 7128 has an exterior diameter that increases gradually from its top, where it has the same diameter as exterior wall 7170 l of inner ring 7166, to its bottom. Extending outwardly from the bottom of keeper 7128 is a peripheral rim 7190 that serves as an abutment for the bottom of the spring.

A recess 7192 is provided in the bottom of keeper 7128 for snugly receiving split ring 7130 that is fitted into groove 7188. To ensure that split ring 7130 does not slide from recess 7192, split ring 7130 is provided with a peripheral groove 7194 at its midpoint into which is fitted an o-ring 7196.

Valve retainer 7134 is segmented, hollow, and cylindrical. The upper segment 7134 u of retainer 7134 is provided with external, helical threads 7198 that screw tightly into a pump.

Valve retainer 7134 has a middle segment 7134 m that is joined to the bottom of upper segment 7134 u. Middle segment 7134 m has a polygonal cross section with six, principal, external faces 7200 separated by six, secondary, external faces 7202 hexagonally arranged. Faces 7200 can be gripped by a wrench for rotating valve retainer 7134.

Valve retainer 7134 has a bottom segment 7134 b that is joined to the bottom of middle segment 7134 m. Bottom segment 7134 b is circular in cross section and has a peripheral slot 7204 around the middle thereof. Slot 7204 accommodates a coupling (not shown) for the quick and easy connection of valve retainer 7134 to a fluid source.

Valve retainer 7134 has a segmented passageway 7206 that conveys fluid through segments 7134 u, 7134 m, and 7134 b into assembly 7112.

After the installation of suction valve 7110 in a pump, a plunger (not shown) is reciprocated above head 7120. As the plunger moves forward to drive fluid from a pumping chamber, the peripheral edge 7178 of head 7120 and valve insert 7010 carried thereon are snugly pressed under the influence of spring 7132 against top surface 7158 t of seat portion 7122 ensuring that no fluid leaks through valve 7110. When the plunger travels back to its starting point, a partial vacuum is created that lifts piston 7118 against the compressive force of spring 7132 and draws fluid upwardly through valve 7110. The process of opening and closing valve 7110 is entirely automatic and requires mere fractions of a second to accomplish.

While valve insert 7010 has been described with a high degree of particularity, it will be appreciated by those skilled in the art that modifications can be made to it. Therefore, it is to be understood that my invention is not limited solely to valve insert 7010, but encompasses any and all valve insert embodiments within the scope of the following claims.

The valve inserts described with respect to FIGS. 43-50 are configured to reduce and correct the improper and laborious maintenance of the pump system.

Recirculating Manifold

Referring now also to FIGS. 51-55 in the drawings, a recirculating manifold is illustrated. Recirculating manifold 8030 is another embodiment of suction or supply manifold 28 described previously. Manifold 8030 receives fluid through a connecting pipe 8032 and equally distributes the fluid through a number of feeders. As seen in FIG. 51, manifold 8030 includes a total of three feeders 8034, 8036, 8038, each used to supply fluid to a suction valve in a fluid end. Manifold 8030 includes a base plate 8057 configured to couple manifold 8030 to a fluid end. Manifold 8030 is configured to optimize the distribution of fluid flow through the three feeders while avoiding dead spaces where fluid can accumulate and cause cavitation, fatigue, and cracks.

Cavitation is caused when fluids that are being pumped vaporize inside the pumps. Vaporized fluids return to liquid form as pressure increases, which causes a vapor bubble collapse in the fluids within and along the inner walls of the fluid ends. These collapsing vapor bubbles produce localized shock waves that break off small amounts of the fluid end's metal walls. These areas along the fluid end walls that are damaged due to cavitation create stress risers that form into fatigue cracks. This results in the fluid ends failing to hold & maintain pump pressure due to pressure leaks through the cracks that have formed in fluid ends. This condition results in the destruction of the fluid ends which are then replaced.

One of the primary causes of pump cavitation is insufficient fluid charge flow into the suction side of the pump. This is typically caused by inadequate suction manifold design. Suspended particles, like sand in the fluid which has been added intentionally as “propants”, can collect & clog a supply manifold, thereby restricting the inlet flow into the pump causing pump cavitation. Manifold 8030 is configured to reduce or eliminate pump cavitation due to inadequate and/or inconsistent charge flow of the fluid. Furthermore, manifold 8030 is configured to reduce and correct the improper operation of pump system 1.

Manifold 8030 includes feeders 8034, 8036, 8038 and interconnects the feeders with pipes and elbows in such a way to permit the fluid to smoothly return back on itself, creating a constant, uninterrupted flow of fluid. As seen in FIG. 51, manifold 8030 is shaped in a “FIG. 8”. It should be understood that other shapes, designs, and configurations of manifold 8030 may be utilized.

Manifold 8030 incorporates a series of pipes and elbows that are in communication with each feeder collectively. Connecting pipe 8032 couples to a radius elbow 8042. Elbow 8042 includes an upper port and a lower port. The upper port feeds a top reducer pipe 8040. The lower port feeds a bottom reducer 8044. Radius elbow 8042, top reducer 8040, and bottom reducer 8044 wrap around a portion of feeder 8034.

Top reducer 8040 and bottom reducer 8044 extend past first feeder 8034 toward second feeder 8036. Top reducer 8040 passes over bottom reducer 8044, not in communication with each other. Bottom reducer 8044 is in communication with second feeder 8036. Top reducer 8040 couples to a short radius elbow 8046. Bottom reducer 8044 couples to a long radius elbow 8048. Elbows 8046, 8048 are each in communication with third feeder 8038.

An important feature of manifold 8030 is the elimination of dead space that leads to the collection of suspended particles. Manifold 8030 is configured to remove dead space where suspended particles like sand can build up and block a pipe. Manifold 8030 does this by removing any endings or terminations in the fluid reservoir, by incorporating periodic bends or elbows in the pipes.

In operation, fluid enters into manifold 8030 and is pulled into the first feeder 8034, but because the volume of fluid entering manifold 8030 is more than first feeder 8034 can handle, the whole manifold becomes filled with fluid, and then the fluid encounters the second feeder 8036 and third feeder 8038. Any fluid that is not pulled in by the third feeder 8038 is then diverted back towards the first pipe. In this way, flow always leads to a pipe, and never leads to a dead space.

A second important feature of manifold 8030 is the reduced area of top reducer 8040 and bottom reducer 8044 and the orientation of angles L₁ and L₂. In particular with FIG. 54, a partial section view of top reducer 8040 is shown. Top reducer 8040 has a feeder area 8043 defined by an axis 8041 a, and a bend area 8045 that extends away from first feeder 8034. Bend area 8045 has an axis 8041 b offset from axis 8041 a. Axis 8041 b bends at an angle L₁ toward the side which first feeder 8034 is located. Angle L₁ can be any angle but it has been discovered that an angle of 37 degrees has some advantages. The reduction in area of top reducer 8040 occurs by partially collapsing the exterior walls of reducer 8040 adjacent first feeder 8034 toward axis 8041 a, while the walls of reducer 8040 opposite first feeder 8034 remain unchanged in direction.

In particular with FIG. 55, a partial section view of bottom reducer 8044 is shown. Bottom reducer 8044 has a feeder area 8047 defined by an axis 8050 a, and a bend area 8049 that extends away from first feeder 8034. Bend area 8045 has an axis 8050 b offset from axis 8050 a. Axis 8050 b bends at an angle L₂ toward the side which first feeder 8034 is located. Angle L₂ can be any angle but it has been discovered that an angle of 37 degrees has some advantages. The reduction in area of bottom reducer 8044 occurs by partially collapsing the exterior walls of reducer 8040 opposite first feeder 8034 toward axis 8050 a, while the walls of reducer 8044 adjacent first feeder 8034 remain unchanged in direction.

The reduced areas assist in overcoming head loss and maintaining the flow of fluid through the pipes and elbows. It is understood that any number of feeders may be used in manifold 8030.

The particular embodiments disclosed above are illustrative only, as the application may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. It is therefore evident that the particular embodiments disclosed above may be altered or modified, and all such variations are considered within the scope and spirit of the application. Accordingly, the protection sought herein is as set forth in the description. It is apparent that an application with significant advantages has been described and illustrated. Although the present application is shown in a limited number of forms, it is not limited to just these forms, but is amenable to various changes and modifications without departing from the spirit thereof.

Rock Screen Insert

Referring now also to FIGS. 56-59 in the drawings, a rock screen insert 8001 is illustrated. Rock screen insert is located within a suction valve 8003, 8005 to filter out large particulates from the fluid received through the supply manifold, like manifold 8030. Rock screen insert 8001 holds a locking mechanism in place and keeping rocks out of the fluid end. In doing so, rock screen insert 8001 described with respect to FIGS. 56-59 are configured to reduce or eliminate pump cavitation due to inadequate and/or inconsistent charge flow of the fluid. Furthermore, rock screen insert 8001 is configured to reduce and correct the improper operation of pump system 1, partly by acting to secure a forward valve guide for the suction valve 8003, 8005.

Fluid flowing from a supply manifold (not shown in FIGS. 56-59) often contain rocks and debris. Rocks that enter the pump through the suction side pose a serious threat to the service life of pump system 1. If rocks pass through with the fluid being pumped, one of two things can happen. If the rocks are small enough, they are crushed by the force of the valve and cause little to no damage to the pump. However, large rocks can do significant damage to the internal components of pump system 1, especially the suction valve. These elements can work inside of the suction valve and get stuck in between the valves and seats, thereby causing damage to the fluid end and cause cavitation problems. Such problems are not derived from inefficient supply manifolds but are an inherent part of the type of fluid being supplied.

Insert 8001 is capable of operating within an assortment of various types of suction valves. For example, FIG. 57 depicts a dual guided suction valve 8005, similar in form and function to that of valve 8230 in FIG. 70, utilizing rock screen insert 8001 a. Additionally a second type of suction valve, suction valve 8003 is depicted in FIGS. 58 and 59 with insert 8001 b. Suction valve 8003 is similar in form and function to that of other suction valve assemblies described in the present application. It is understood that other valves and configurations are possible. It is understood that insert 8001 may be used on a variety of fluid ends, such as any of those describe in this application or others within the scope of the application.

Insert 8001 forms a barrier across the full inner diameter of the suction valve. As seen in FIG. 56, insert 8001 is configured to have apertures 8009 along a top surface 8011 that allows small rocks to pass through, but catches any rocks too big to be crushed by the valve. Apertures 8009 consist of an assortment of shapes and sizes. Some apertures 8009 are elongated cylinders or circular. It is understood that the orientation and design of apertures 8009 are capable of being adjusted. These apertures filter out the rocks and debris in the fluid. Any rocks caught by the rock screen are easily removed from the pump during routine inspections of the fluid end. It should be understood that other shapes, designs, and configurations of the rock screen inserts may be utilized.

Insert 8001 may be located in any location within the suction valve assembly prior to the valve 8007 a, 8007 b. Suction Valve 8003 includes a spring retainer and valve stop 8015, valve guide 8013, and valve 8007 a. Furthermore, a valve guide 8017 and valve stem 8019 are illustrated and serve to guide movement of valve 8007 a. As valve 8007 a is actuated from the pressure differential of the reciprocating plunger (not shown in FIGS. 56-59), valve 8007 a presses against valve seat 8021. A suction nut 8023 is threadedly coupled to the fluid end 8002 and maintains a manifold connection 8025 to couple to the supply manifold for receiving fluid.

Suction valves 8003, 8005 are double guided, with front and rear guides working together to ensure straight and consistent movement of the valves. The rock screen insert 8001 helps maintain the front guide so the valve has straighter travel and better consistency. A locking mechanism is used for easy installation and removal. The locking mechanism keeps the valve assembly in place during pumping as well as ensures against premature valve failure due to erosion and wear. This locking mechanism is made secure in part due to the finished edges of the rock screen insert, which are machined for this particular purpose.

Insert 8001 is designed to be as low maintenance as possible. Collected rocks on top of the suction guides are removed automatically when the valves & seats are changed simply because the covers are removed during the standard valve and seat change outs and operators will instinctively dump and knock them off the covers before they re-install them back into the fluid ends.

Packing Nut Assemblies

Referring now to FIGS. 60-67 in the drawings, individual alternative embodiments of a packing nut are illustrated. The packing nuts described herein are designed to eliminate the problems caused by the need to manually set & adjust packing nuts by providing automated control through pressure regulation and monitoring.

Packing nuts described in FIGS. 60-67 are each configured to reduce and correct the improper and laborious maintenance of the pump system 1, and the improper operation of pump system 1. This is done by accomplishing at lease three objectives: 1) properly sealing the plunger chamber to create pressure; 2) adequately lubricating the plunger to prolong the life of the packing nut and plunger as they are in friction contact through the reciprocating movement; and 3) sufficiently removing heat through the gradual controlled leakage of lubrication through the packing nut.

Packing nut 8060 includes a body 8062, a bellows 8064 having an internal wall 8064 a and an outer wall 8064 b, a nose ring 8066, and a pressure port 8068. Body 8062 threadedly couples to the fluid end. Body 8062 is threadedly coupled to the fluid end. The threads may vary in size and count to permit retrofit applications on existing pump systems. The plunger translates along an inner surface 8070 of body 8062. Seals 8072 are provided to prevent leakage between the plunger and body 8062.

Nose ring 8066 is freely coupled to body 8062 by bellows 8064. Internal wall 8064 a and outer wall 8064 b are affixed to nose ring 8066 and body 8062 in a pressure holding connection which can be either welded seam or a mechanical rolled seam design. An annular volume is created between the walls 8064 a and 8064 b, thereby creating a piston area that translates the nose ring concentrically along an axis 8072 of body 8062 when hydraulic pressure is applied through pressure port 8068. Nose ring 8066 applies a compression load to the packing element is attached to the other end of the bellows in the same manner as described above. Pressure port 8068 is configured to pressurize bellows 8064 as needed. An existing lube system is used to provide pressurized lube to packing nut 8060 through pressure port 8068.

Referring now also to FIGS. 62-64 in the drawings, a second embodiment of a hydrostatic packing nut is illustrated. Packing nut 8074 is similar in purpose, form and function to that of packing nut 8060 except as described herein. Packing nut 8074 uses hydraulic forces to transmit an accurate compressive load that serves to seal the plunger and fluid end bore. The actual compressive forces can be directly read from a pressure gauge or transducer as opposed to theoretical forces generated by screw type only threaded packing nuts, which cannot be accurate due to frictional losses that exist in the thread at any given time.

Packing nut 8074 is seen in FIG. 62. A cross section of packing nut 8074 is illustrated in FIG. 63. Packing nut 8074 is configured to allow for automated adjusting while pump system 1 is in operation. Furthermore, packing nut 8074 is configured to allow for safe and accurate adjustment of the packing set over the full operating range of the fluid end.

The packing nut assembly 8074 includes an outer threaded body 8076, an inner packing adjustment piston 8078, an outside diameter hydraulic seal 8082, and an inside diameter hydraulic seal 8080. Body 8076 includes a pressure port 8084 that receives variable pressure from an external source. Threaded body 8076, along with the inner packing adjustment piston 8078, are coupled to the fluid end in a threaded relationship. Hydraulic pressure is regulated through pressure port 8084 and hydraulic fluid is captured between the sealing elements 8080 and 8082. The annular volume between sealing elements 8080 and 8082 creates a piston area that causes linear movement of the adjustment piston 8078 when hydraulic pressure is applied.

Outward movement of piston 8078 pre-loads the packing nut 8074 just as screwing the conventional packing nut inward on the threads creates a preload. The advantage with packing nut 8074 is the ability to set the packing load from a remote location through the remote regulation of hydraulic pressure. Additionally, nut 8074 may include the use of a monitor 8086 to allow the advantage of monitoring the operating load that the packing is experiencing via feed back from the hydraulic pressure changes while the system is in operation. Monitor 8086 is configured to provide an operator of pump system 1 operational feedback concerning the condition of nut 8074.

End point adjustment for packing wear can be set by adjusting the amount of travel left where the small diameter of the packing adjustment piston 8078 passes under sealing element 8080. When the travel allows the piston to go past the sealing element 8080 the hydraulic pressure is lost signaling that the packing element has been compressed and worn to the end of its service life.

Packing nut 8074 allows dynamic adjustment and pressure monitoring throughout the entire operating range of the fluid end. This allows the packing elements to run at their optimum compression loads for any given pressure setting. Since the packing elements are running neither in an under or over compressed state the service life will increase.

Referring now also to FIGS. 65-67 in the drawings, a third alternative hydrostatic packing nut 8088 is illustrated. Packing nut 8088 is similar to that of nut 8074 and 8060 except that nut 8088 provides the same operating effects without additional moving parts.

The packing nut 8088 is a one piece unit that uses two seals 8090 and 8092 to prevent the hydraulic pressure that is introduced through a pressure port 8094 from escaping to atmosphere either around the plunger or around the packing bore in the fluid end. Being captured, the pressure is forced to react against the packing assembly to produce axial and radial energizing pressure against the packing nut 8088 causing sealing against the plunger and fluid end packing bore.

Packing nut 8088 is in communication with a variable pressure hydraulic source 8096 through port 8094. Packing nut 8088 may be in communication with a sensor 8098 to monitor the pressure within nut 8088. An operator is able to regulate and monitor the pressure of nut 8088. As with nut 8074, a loss of hydraulic pressure may be experienced which would signal the end of nuts 8088 useful life.

Dual Guided Valves

Referring now also to FIGS. 68-75 in the drawings, alternative embodiments of valve guides are illustrated. There are six types of valve guides used on fluid ends 10, 410, 4012 as seen in FIGS. 11-16. Fluid ends 10, 410 use guides that mate with stems which are on the back sides of the valves. The suction valve stem is part of the suction valve & the discharge stem is a separate part from the discharge valve. Fluid end 4012 uses dual guided valves that mate with stems which are on both sides of the valves. Fluid end 4012 has more guide types because even though fluid end 4012 uses the same valves & seats for both the suction & discharge sides, fluid end 4012 uses different guides on each of the four stems, (two on suction & two on discharge).

FIG. 68 shows a discharge valve guide assembly 8200 for use in a discharge valve of a fluid end similar to fluid end 4012. Valve guide assembly 8200 includes a front discharge valve guide 8202, a valve 8204 with an upper guide stem 8206 and a lower guide stem 8208, a spring 8210, a rear discharge valve guide 8212. Front guide 8202 mates with lower guide stem 8208; on the front of the discharge valve 8204, the front guide 8202 positions under seat 8214 & registers to align using the seat deck bores. Rear guide 8212 is mounted in the discharge cover 8216 which also serves as a valve spring 8210 retainer & valve stop.

In particular with FIG. 69 a suction valve guide assembly for use in a suction valve of a fluid end similar to fluid end 4012 is illustrated. Valve guide assembly 8230 includes a front suction valve guide 8232, a valve 8234, a spring 8236, and a rear suction valve guide 8238. Front guide 8232 is designed to deal with the position of the valve which is beneath the plunger. Rear guide 8238 is also configured to be a spring 8236 retainer & valve 8234 stop while at the same time permitting fluid to flow around it.

Front guide 8232 of suction valve guide assembly 8230 is configured to serve as a seat retainer & due to the limited accessibility. Front guide 8232 also includes a locking mechanism 8240 to automatically lock & retain the seat of front guide 8232 when the valve was installed and automatically unlock the seat of front guide 8232 when the valve were removed. The locking mechanism 8240 is configured to permit the installation and removal of valve 8234 with a single hand. Locking mechanism also includes a shaft 8242, a set spring 8244, and a set screw 8246. It is understood that other types of locking mechanisms may be used and are contemplated herein.

As seen in FIG. 70, discharge valve guide assembly 8200 and suction valve guide assembly 8230 are illustrated within a fluid end. Suction valve front guide 8232 doubles as the seat retainer using the locking mechanism 8240 which locks as the valve is installed & unlocks as it is removed. The rear suction valve guide 8238 uses a locating diameter in the fluid end to center the guide in line with the suction bore. The rear guide 8238 also functions as a spring retainer & valve stop. Plunger chamber 8248 is illustrated as running perpendicular to a line between the valve assemblies 8200 and 8230. A packing side 8250 of plunger chamber 8248 is configured to receive a packing nut similar to any of those described in the application, in particular with FIGS. 60-67. Opposite packing side 8250 is a suction cover side 8252.

With respect to valve guides used in fluid ends 10, 410 as described in FIGS. 11-14, FIG. 71 illustrates a discharge valve guide 8270 as well as a discharge valve 8272 similar to piston 106 in FIG. 12D. Valve 8272 is shown with a valve insert 8274 similar to insert 7010 in FIG. 43. Valve 8272 includes a hollow elongated shaft 8276 located behind a head portion 8278 of valve 8272. The hollow feature 8273 of shaft 8276 is configured to accept a stem 8280 protruding from valve guide 8270. Slots 8282 are formed in shaft 8276 for sand evacuation. It is preferred for there to be a total of four slots 8282 in shaft 8276 but more or less is possible. Stem 8280 has a fluted tip for channeling the sand away that may build up in between the stem 8280 and valve 8272.

Discharge valve guide 8270 is configured to also function as the seal/cover for the discharge bore in the fluid end, in addition to the valve spring retainer & the valve stop. Stem 8280 is configured to rest within the hollow feature 8273 thereby permitting translational movement of discharge valve 8270. As valve 8270 actuates the movement is controlled & regulated by the guide stem 8280 which maintains the position of the valve 8270 centrally in line with the valve seat.

Referring now to FIGS. 72-76 a suction valve assembly for use in fluid ends 10, 410 is illustrated. Suction valve guide assembly 8290 includes at least a suction valve guide 8292 adjacent a suction valve seat 8294, a suction valve 8296, and a locking mechanism 8302. The valve spring has been omitted to show the guide 8292 more clearly in FIGS. 72-73. Suction valve 8296 is another embodiment of associated portions of the suction valve 5010 described in FIGS. 38-40. Suction valve 8296 is similar in form and function to suction valve 5010 except as noted herein. There are at least two changes with the suction valve assembly of FIG. 38: 1) changes to the valve itself; and 2) changes to the guide.

The changes made to the valve 5010 in FIGS. 38-40 affect the valve keeper 5028, split ring 5030, O-ring 5096, knob 5086, and stem 5024. These items corporately perform four functions as follows, retain the valve spring, Retain the valve inside the valve retainer or suction nut 8300, regulate the amount the valve can open during actuation (also called valve stoke & valve stop), and provide the ability to remove, change, service and assemble the valve into the valve assembly & fluid end.

With respect to changes to the suction valve itself, suction valve 8296 has lengthened stem 8298 by removing the valve keeper 5028 and stop groove 5088 seen in FIG. 38. Stem 8298 is partially threaded adjacent the end opposite the valve head. A retainer groove 8308 is located above threaded portion 8304 for engaged contact with a spring retainer and valve stop 8015.

Suction valve 8296 includes a locking mechanism that includes quick lock and release valve retainers designed to eliminate the need for complicated locking mechanisms (including roll and cotter pins) currently used to retain suction valves and spring assemblies in fluid ends. The locking mechanism prevents the threads from backing out/coming loose and is a portion of the one piece threaded spring retainer/valve stop 8015. Spring retainer and valve stop 8015 include a retainer 8302 and a valve stop 8305. Retainer 8302 is threadedly fastened to stem 8298 along threaded portion 8304. Valve stop 8305 includes a rotatable hook 8306 that is selectively rotated such that the hook 8306 portion engages groove 8308 to lock and secure valve 8296.

Suction valve 8296 is configured to permit installation and removal of suction valve assembly 8290 with a single hand. The spring retainer, valve retainer, valve removal knob & valve stop groove located on the valve stem area, have been combined into one assembled part, suction valve 8296.

The changes made and incorporated into this portion of valve 8296 and valve assembly 8290 do not change the way the valve 8296 functions mechanically with respect to valve 5010. Valve 8296 still uses the same guide method, stroke distance, seal areas, spring force, etc. These changes are made to simplify the design, reduce costs, and provide better ease of assembly and maintenance, while performing the same objectives & purposes of the original design, seen in FIGS. 38-40.

With respect to the valve guide, valve guide 8292 is positioned central to the seat 8294 locating on the counter bore diameter on the back of the seat 8294. Valve guide 8292 includes a filter insert similar in form and function to a rock screen insert described in FIGS. 56-59. This filter is to prevent rocks & other large debris from entering the fluid end which often times would get stuck between the valve & valve guide which would lead to jetting & damage to valves, seats, & fluid ends. The stem 8298, in this embodiment, is part of the suction valve 8296 and passes through the guide 8292 up until the spring retainer and valve stop 8015. FIG. 76 shows a completely assembled suction valve assembly 8290 outside of a fluid end.

The valve assemblies described with respect to FIGS. 68-76 are configured to reduce and correct the improper and laborious maintenance of the pump system.

Straight Seals and Peanut Shaped Intersections

Referring now also to FIGS. 77-79 in the drawings, an alternative embodiment of the tapered seats in a fluid end is illustrated. A high pressure straight seal 8320 is illustrated in various figures throughout the application, namely FIG. 68 (#8214), FIG. 69 (#8232), and FIG. 57 to name a few. Although the numerical identifier for seal 8320 is different in FIGS. 77-80, it is understood that prior Figures used in this application may be used to assist in ascertaining the forms, functions, and any limitations of seals 8320 described herein this section.

Seal 8320 include at least a straight seat 8322 and a retainer 8324. Seal 8320 allows seats to be installed in fluid ends without needing seat tapers, which were previously needed to insure a metal to metal contact between the seats & seat tapers in fluid ends so that the seats would have tight seals under pressure. Where taper seats are exposed to high pressures, the taper seats are pushed with such great force into the fluid ends that they become stuck needing extreme force to remove them. Hardened taper seats can act as wedges that damage the expensive fluid ends by pushing & distorting the walls of the fluid end. This is also compounded when fresh hardened taper seats are installed to continue the distortion where the previous seats left off, in effect sharpen the pile driver wedge & keep going.

Seals 8320 also can include a seal made using a combination of urethanes that is proprietary blend. The seals have a greater temperature & corrosive chemical exposure operating range & they do not need the same special storage & handling requirements that O-rings in tapered seats have. O-rings on taper seats are low pressure seals & only allow the pump to build up pressure & then the metal contact area on the tapers is designed to take over as the pump reaches higher pressures pushing the wedged metal sides of the seat & seat taper which is inside the fluid end against each other.

Straight seals 8320 are high pressure seals which eliminate the need for taper seat decks & taper seats by sealing at high pressures in a straight bore within the fluid end, not a taper wedge using metal to metal contact. This allows the fluid end to remain undamaged, the seats to be installed & removed with minimal force, faster valve & seat changes, longer valve & seat life, & longer fluid end life. Seals 8320 may be used in any fluid end such as those described in this application.

An additional feature and benefit of seals 8320 is the inclusion of retainer 8324. Retainer 8324 is coaxial with seat 8322 and slides over an external surface of seat 8322. Retainer 8324 contacts a ledge within the valve assembly, thereby restricting undesired translation of the valve 8326 and seat during promotion of the plunger. Seals 8320 are rated to 50,000 psi with service life spans up to 1500 hours in the frac applications. Current Frac pressures peak at 15,000 psi.

Seals 8320 are configured to reduce stress concentrations within the fluid end assembly by distributing forces generated against the valves over a larger surface area as compared to taper seats. Seal 8320 is configured to reduce metal fatigue in the fluid end and increase ease of maintenance. Furthermore, seal 8320 is configured to reduce and correct the improper and laborious maintenance of the pump system.

FIG. 78 illustrates the seal 8320 used in fluid end 10, 410. Fluid end 10, 410 has an alternative suction seat seal deck 8328 and an alternative discharge seat seal deck 8330. Suction seat straight seal 8332 is configured to contact deck 8328 in the suction valve. Suction seat straight seal 8334 is configured to contact deck 8330 in the discharge valve. FIG. 79 illustrates a suction seat seal deck 8336 and a discharge seat seal deck for use in fluid end 4012.

Referring now also to FIGS. 80A and 80B in the drawings, schematics of the vertical passage with sectional views showing the shape of the passage from front, side & top views is illustrated. Fluid ends 10, 410, 4012 (any all other fluid end embodiments herein described) are modified to include selectively tailored peanut shaped bores or cut outs at the intersections of the suction valve, discharge valves, and plunger chamber. It is understood that modified bores may be included in other locations within pump system 1, for example in the recirculating manifold.

The peanut shape redirects the stress forces that normally build up around the main intersection into the stronger main core area of the fluid end, similar to a detour for traffic, the stress follows the peanut shape curves away from & around the intersections instead of flowing & concentrating into them.

The Peanut shape intersection uses six separate cylindrically shaped cut outs that are applied to a cylindrically shaped bore intersection where two cylindrically shaped bores intersect perpendicular & central to each other also called a “tee” intersection, as seen in fluid end 4012. Four of the cylindrically shaped cutouts are applied in the horizontal axis & the other two are applied in the vertical axis. The Horizontal axis appears to take the form similar to the shape of a peanut when viewed in line with the horizontal axis. The vertical axis appears to take the shape of an oval when viewed in line with the vertical axis. The tee intersection where the bores & cylindrically shaped cutouts meet takes a form that has features from the combined bores & cylindrical cutouts.

As seen in FIG. 80, The two vertical cylindrical cut outs 8344 are formed from the bottom suction side 8340 (opposite discharge side 8341) & stop when they reach the center line 8342 of the tee intersection 8350 where they end with spherically shaped radiuses 8346, (not sharp corners) & do not continue passed the intersection in the vertical passage. In the same manner the four horizontal cutouts 8348 are formed from the suction cover side & stop when they reach the center line of the tee intersection 8350 where they end with spherically shaped radiuses 8346, (not sharp corners).

Software is used to detect weaknesses in the fluid ends and optimize the size, depth, and types of bores or cut outs used to reduce stress concentrations. It is understood that although peanut shaped bores have been described with respect to a single embodiment of a fluid end, any fluid ends contemplated within the scope of this application are capable of using the peanut shape bores or cut outs.

Combining Peanut shape intersections & straight seat decks in the fluid end design used in pump system 1 strengthens the fluid end which lengthens the service life of the fluid end by up to 75%. Combining straight seat decks & peanut shape intersections in the same fluid end increases the fluid end life by eliminating the concentrated stress areas that form around the intersections & seat decks in fluid ends that use taper seat decks along with standard cylindrical intersections. Combining Peanut shape intersections & straight seat decks in the fluid end design together increases life expectancy beyond that expected with the use of either one individually.

It should be noted that the individual components and parts of the pump system described herein are individually configured to improves pump efficiencies and service life; but when combined into one pump system, the components and parts of the pump system described herein work together to produce the highest efficiencies and longest service life.

The present application provides significant advantages, including: (1) reduced pump cavitation due to inadequate and/or inconsistent charge flow; (2) reduced cracking and failure die to metal fatigue in the pump system fluid ends; (3) reduce and correct the improper and laborious maintenance of the pump system; and (4) reduce and correct the improper operation of the pump system.

While the preferred embodiment has been described with reference to an illustrative embodiment, this description is not intended to be construed in a limiting sense. Various modifications and other embodiments of the application will be apparent to persons skilled in the art upon reference to the description.

The particular embodiments disclosed above are illustrative only, as the application may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. It is therefore evident that the particular embodiments disclosed above may be altered or modified, and all such variations are considered within the scope and spirit of the application. Accordingly, the protection sought herein is as set forth in the description. It is apparent that an application with significant advantages has been described and illustrated. Although the present application is shown in a limited number of forms, it is not limited to just these forms, but is amenable to various changes and modifications without departing from the spirit thereof. 

What is claimed is:
 1. A pump system, comprising: a power end assembly having a pony rod; a fluid end assembly having a plunger for generating an alternating pressure differential in the fluid system, the power end being configured to induce translation of the plunger within the plunger chamber to pressurize a charge fluid; a suction valve assembly and a discharge valve assembly configured to selectively operate in response to the pressure differential; and a straight valve seal configured to seal the suction valve assembly and discharge valve assembly in a straight bore within the fluid end assembly.
 2. The pump system of claim 1, wherein the power end includes a multi-piece connecting rod configured to use a plurality of threaded fasteners to couple individual portions together to reduce wear of the connecting rod.
 3. The pump system claim 1, wherein power end includes a connecting rod bearing housing in communication with a connecting rod, the bearing housing including a channel and associated bevel area for the distribution of lubrication.
 4. The pump system claim 1, wherein the plunger and the pony rod are coupled together via a pony rod adapter.
 5. The pump system claim 1, wherein the pony rod adapter is a dove-tail clamp.
 6. The pump system claim 5, wherein the pony rod adapter uses a non-threaded relationship to couple the pony rod and the plunger together.
 7. The pump system claim 1, wherein the suction valve and the discharge valve are intersect a centerline of the fluid end at an obtuse angle, the centerline being coaxial with an axis of the plunger.
 8. The pump system claim 1, wherein the suction valve defines a first centerline and the discharge valve defines a second centerline, the first centerline and the second centerline being parallel with each other and perpendicular to a third centerline defined by the plunger.
 9. The pump system of claim 1, wherein the suction valve assembly includes a seat portion and a guide portion configured to properly align the valve.
 10. The pump system of claim 1, wherein at least one of the suction valve assembly and the discharge valve assembly includes a valve insert to seal a valve opening.
 11. The pump system of claim 1, further comprising: a recirculating manifold having a reducer configured to optimize the distribution of charge fluid through a feeder, the feeder coupled to a suction valve assembly.
 12. The pump system claim 1, further comprising: a rock screen insert configured to filter out particulates from the charge fluid; the rock screen insert being located within the suction valve assembly.
 13. The pump system of claim 12, wherein the rock screen insert maintains a front valve guide to improve performance of the suction valve assembly.
 14. The pump system of claim 1, wherein the fluid end assembly includes a packing nut configured to seal around the plunger, the packing nut configured to receive automated adjustment during operation of the pump system.
 15. The pump system of claim 1, wherein the packing nut includes a monitor to provide an operator operational feedback concerning the condition of the packing nut during operation of the pump system.
 16. The pump system of claim 14, wherein the packing nut includes a bellows forming an annular volume for reception of a working fluid configured to regulate the pressure on the packing nut.
 17. The pump system of claim 14, wherein the packing nut includes an annular volume between a piston and a body for reception of a working fluid configured to regulate the pressure on the packing nut.
 18. The pump system of claim 1, wherein the suction valve assembly and the discharge valve assembly are configured to accept a dual guided valve.
 19. The pump system of claim 1, wherein the suction valve assembly includes a locking mechanism configured to permit removal of a suction valve with a single hand.
 20. The pump system of claim 1, wherein the fluid end assembly is configured to receive bores and cutouts configured to reduce stress concentrations within a fluid end. 